Document JrjE6ZY944g4eyLvwyvbE50nZ

UNITED STATES DEPARTMENT OF THE INTERIOR HAROLD L. ICKES, Secretory BUREAU OF MINES JOHN W. FINCH, Director Bulletin 403 PLAINTIFF'S EXHIBIT CAP-1475 ASBESTOS BY OLIVER BOWLES t fcf* " 1 UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON i 1937 For ..I. by th. Superintendent of Document., W..hIntton, D. C. Pries 15 cents 'l ASARCO ALV 0006244 CONTENTS Introduction------------------------------ Definition---------------------------------- Varieties---------------------------------physical properties------------------- Outstanding characteristics__ Fibrous character Fineness of fiber------------------Color and luster Heat resistance_____________ Heat conductivity Acid resistance Electrical resistance................ Specific gravity Chemical composition Svnthetic asbestos History....................................... .. Early records History of commercial pro duction.................................. History of asbestos product manufacture Origin Mode of occurrence Uses..................................... ......... General distribution Production and consumption___ History of production in the United States World production World consumption Domestic deposits Chrysotile Alaskai. Arizona California Montana Oregon........ ........................... Vermont Wyoming Other occurrences Amphibole Alaska................................ .. California Georgia.................. ............. .. Idaho________________ ____ Maryland Montana.......................... .. North Carolina............. ....... Oregon.......... ................... ..... Texas.......... ........................... Virginia...... ..................... ..... Washington Other occurrences Face Piz 1 Foreign deposits____ __________ 1 Canada_____________________ 1 2 2 o 3 3 3 3 4 4 4 4 Rhodesia___________________ Union of South Africa_______ Cape of Good Hope_______ Transvaal_________ Chrysotile______________ Amosite........ ................. Crocidolite_____________ Anthophytlite___________ Natal'.___________ Other African occurrences___ Soviet Russia_______________ 5 Italy__________________ 5 Cyprus________ 30 30 34 36 37 37 37 39 39 39 39 40 40 42 43 5 Other foreign deposits......... ... 44 Argentina________ _______ _ 44 7 Australia_________________ 45 Western Australia........... 45 8 South Australia. .................. 45 10 Queensland............................ 46 11 New South Wales . .......... 46 11 Tasmania_________________ 46 14 Austria.............. 46 15 Brazil_________ ________ 46 Bulgaria............. ................. .. 47 15 China__________________ 47 16 Czechoslovakia......... ....... .. 47 17 Finland__________________ 47 19 France______________________ 48 19 Germany_____ _____........... 48 49 India.-I________________ 48 20 Ireland_____________ 49' 21 Mexico____ ______________ 49 23 Newfoundland...................... 49 23 New Zealand______________ 49 24 Philippine Islands.................... 49 25 Portugal........................... 49 25 Spain___________________ _ 49 26 Switzerland_____________ 49 26 Turkey__________________ 50 26 Venezuela__________________ 50 26 Other countries.................... 50 27 Political and commercial control. 28 Political control_____________ 50 50 23 Commercial control . 51 28 International trade______________ 51 29 Exports from principal pro 29 ducing countries__________ 51 29 Imports into the United States. 54 29 ExportsfromtheUnitedStates. 53 30 Prospecting and exploration____ 59 m ASARCO ALV 0006245 IV CONTEXTS Mining methods. Arizona______ Vermont_____ Georgia and Maryland. Canada. ....___ _________ Rhodesia............................... Union of South Africa......... Russia............ ...................... C-vprus............. .................... China____________________ Miliine methods......... ............ Classification of fiber______ General features of milling methods_______________ Canada__________________ Preparation of crudes___ Milling practice................ Preliminary crushing... Drying_______________ Storage.......................... Fiberizing____________ Screenine...................... Air suction___________ Vet process__________ Grading......................... Classification_________ Arizona__________________ Vermont......... ............... ....... Union of South Africa......... Chrvsotile.......................... Crocidolite_____________ Amosite............................ Rhodesia_________________ Russia................................... Cvprus............. ..................... Australia_________________ Vapt*! 59 Milling methods--Continued. 59. Ar.tnopnyliite milling.............. 60: Marketing______ _____________ 00' 00' 62 62 63 63 Prices........... ................................. Manufacture of asbestos prod ucts A widespread and diversified industry 64 Ashcstos-products plants 64- United States Canada I Great Britain______ ______ Germany 66. Austria 60; France 66! Belgium 66! Italy....................................... 66 i Czechoslovakia 67, Netherlands 67 i Finland.................................. 6S: Scandinavia 68 Australia_________________ 68- Russia.................. ................. 69: Other countries 69! Fabrication of asbestos prod 711 ucts 70 ! Fabrics 72! Shingles and lumber 721 Paper and millboard........ 731 Compounded packings 74 i Magnesia insulation 74! Asbestos cement 75| Cold-molded articles Noncorrosive filters 77 ISSelected bibliography Fa rt 7i> 79 S2 S2 82 82 85 So 85 85 SO 80 SO 80 86 SO 86 87 S7 87 87 87 89 89 90 90 90 90 91 91 ILLUSTRATIONS Fir. 1. Typical cross-fiber veins of Canadian asbestos_____________________ 2. Asbestos consumption compared with automobile production and building construction, 1926-36.._______ 3. Asbestos production in the three leading foreign centers and in the United States, 1916-35 4. Crude chrvsotile asbestos from Arizona 20 5. Veins of asbestos on drift face 500 feet below surface, Thetford Mines, Quebec 30 6. Asbestos veins in the New Amianthus mine, Barberton district, Transvaal, South Africa 3S 7. Steel chutes and chain-chute gates, Asbestos Corporation, Ltd., mine, Thetford Mines, Quebec__________________ 8. Mill of Vermont Asbestos Corporation near Eden, Vt_______________ 9. Average value per short ton of Canadian crudes and spinning fibers, 1921-35.................................................................................................... 10. Average value per short ton of Canadian single, millboard, and paper stocks, 1921-351______________________ 10 14 17 60 72 SO 81 i By C IK The mineral asbestos, bee: allied to cotton and wool b resistance; therefore, it sup- no substitutes are yet avail- features of the asbestos indi mining, milling, utilization, i United States leads all cou products, but domestic soure raw material required. As great an extent on foreign deals at length with tiie iTsbe Several reports now availa countries. Among them are Ross; Asbestos in"the Union series of articles on the Rusi These have been drawn upi hereby made for the helpful the magazine Asbestos-a Iso li ing all phases of the industr; in the bibliography at the ! and have been supplemented with the industry for t concise, world-wicle. hisu.,,ei the asbestos industry. " 1- "Asbestos" is not the nan rather, a commercial term ap crals. These minerals diffei are diverse in strength, flexi The following varieties oi Chrysotile is a hydrous n represented by the chemical composition as massive serpe Chrysotile is characterized b 1 Work on manuscript completed Jai 1 Assistant chief engineer. Nonmeta l ASARCO ALV 0006246 XEJXENTS nit 39 Milling methods--Continued. 59 Anthophyllite milling---------- 60- ''arketing............................... . 6 ices... & <52 <52 Afcinufacture 'of "asbestos products......... ............... A widespread and diversineit <53 <53 64 64 64 industry--------------------------- `Asbestos-products plants......... Cnited States....................... Canada----------------- - Great Britain........................ 03 66 66 66 66 66 67 6 6S 63 6S 69 Germany-------------------------- Austria......... ........................ France----------------------------- Belgium...... ....................... -- Italy.............. - Czechoslovakia---------- ...... Netherlands.................. ........ Finland---------------------------- Scandinavia Australia--------------------------- Russia Other countries..................... 69 Fabrication of asbestos prod 71 ucts 72 Fabrics 72 Shingles and lumber 72 Paper and millboard 73 Compounded packings 74 Magnesia insulation 74 Asbestos cement Coid-molded articles Noncorrosive filters Selected bibliography Fage 11 7S 79 82 S2 82 82 85 85 85 85 86 86 86 86 86 56 86 87 87 87 57 87 89 89 90 90 00 90 91 91 '3TRATION3 ldia. oestos______________________ ;d with automobile production and 5................................................................ se leading foreign centers and in the ................................................................ Arizona 20 10 feet below- surface, Thetford Mines, ................................................................. iiuianthus mine, Barberton district, .................................... :es. Asbestos Corporation, Ltd., mine, ............. -..............-......................... ration near Eden, Vt_______________ Canadian crudes and spinning libers, ....................................................... Canadian single, millboard, and paper ................................................................ 10 14 17 30 3S 60 72 SO 81 ASBESTOS1 By Olives Bowles 1 INTRODUCTION The mineral asbestos, because of its unique fibrous character, is allied to cotton and wool but has the advantage of heat and fire resistance; therefore, it supplies many industrial needs for which no substitutes are yet available. This report covers the essential features of the asbestos industry, including occurrence, production, mining, milling, utilization, international trade, and marketing. The United States leads all countries in the manufacture of asbestos products, but domestic sources furnish only a small fraction of the raw material required. As the United States is dependent to so great an extent on foreign supplies of raw materials, the bulletin deals at length with the asbestos industrv in foreign lands. Several reports now available deal with the industry in individual countries. Among them are Chrvsotile Asbestos in Canada, by J. G. Boss; Asbestos in'the Union of South Africa, bv A. L. Hall:" and a series of articles on the Russian industry, by "Walter A. Ru Keyset-. These have been drawn upon freely, and full acknowledgment is hereby made for the helpful information thus secured. The file of the magazine Asbestos also has furnished many valuable data touch ing all "phases of the industry, ifany other books and articles listed in the bibliography at the end of this bulletin have been utilized and have been supplemented by the author's intimate acquaintance with the industry for-about 26 years. The intent is to present a concise, world-wide, historical, technical, and economic treatment of the asbestos industry. DEFINITION "Asbestos" is not the name of a distinct mineral species but- is. rather, a commercial term applied to fibrous varieties or several min erals. These minerals differ widely in composition, and the fibers are diverse in strength, flexibility, and consequent usefulness. VARIETIES The following varieties of asbestos are generally recognized: Ghrysotile is a hydrous magnesium silicate, a fibrous~serpentine. represented by the chemical formula H,Mg3Si-0,. It has the same composition as massive serpentine, with which it is always associated. Chrysotile is characterized by a strength and flexibility that permit 1 Work on manuscript completed Jan. 26. 1937. "Assistant chief engineer. Nonmetal Economics Division, TJ. S. Bureau of Mines. 1 * * 'I ASARCO ALV 0006247 9 ASBESTOS the use of the longer fibers for spinning. The bulk of the world 2>roduction of both Jong iind short fibers is of this variety. Ocher varieties of asbestos belong to the nmphibole group of min erals. Anthophi/lUte. having the composition (Fe.Mg)SiO.,. is the type most- abundant in the United States. Usually, it is brittle and of low tensile strength and is more resistant to the action of acids and heat than chrvsotile. It is used for nonspinning purposes. Amosite. a variety of iron-rich anthophyllite occurring in Africa, has unusually long fibers. The best-grade material is used for spinning. Crocidolite. also called "blue asbestos", having the composition NaFe(Si03)2Fe5i03, occurs in commercial quantities chiefly in Africa. It is used for both spinning and nonspinning purposes. Crocidolite occurring in quartz is sol'd as the semiprecious l,tigereye." Fibrous tremolite, CaMg^SiCh)... actinolite. Ca(MgFe).(Si03)4. and hornblende, a complex silicate similar in composition to actino lite, generally are regarded as the minerals to which the term "asbestos" was applied originally. Except for Italian tremolite, they have little commercial value. Mountain leather and mountain cork are varieties of amphibole consisting of flexible sheets of interlaced fibers. Mountain wood is a compact fibrous mass of amphibole resembling dry \vood._ The last three varieties are mineral curiosities and have no commercial value. PHYSICAL PROPERTIES OUTSTANDING CHARACTERISTICS The most characteristic properties of asbestos--those that give it commercial value--are fibrous structure and fire resistancef The longest and strongest- fibers have qualities possessed by no other min eral. in that they may be spun into yarn or thread, woven into cloth, or felted into sheets and packings in almost the same way as animal and vegetable fibers, but unlike cotton or wool, they' consist of incombustible matter. FIBROUS CHARACTER Although all asbestos is fibrous, the quality of the fiber in the various types and in different deposits is quite diverse. Chrvsotile. amosite, and crocidolite normally possess high tensile strength, flexi bility. and elasticity, but- these qualities vary greatly in material from different localities. Chrvsotile occasionally is harsh and somewhat brittle. _ Crocidolite is said to be stronger than chrvsotile. The fibers of amosite are exceptionally long. Anthophyllite Is generally brittle and of low tensile strength, although the fiber from some deposits lias considerable strength'and toughness. This type usually is more flexible than fibrous tremolite or actinolite. Tremolite is generally too weak and brittle for textile use; Italian tremolite, however, is said to be of spinning grade. Length of fiber is important in asbestos strong and flexible enough for spinning and weaving. The fiber is graded on the basis of length, and materials of identical quality may range in price from $20 to $500 a ton. according to length. Fineness of fibe" ;s plished by fiberi is due to a highly ucve cleavage planes being size of the ultimate ] Subdivision, therefore definitely, the fineness of the to'ols used and t Varieties of asbestc markedly in the ease ' can be separated readi with difficulty and the rill has measured ant eter.s and the stnalle 0.00075 mm.-1 Apartasbestos is measured t able and by the amot fineness desired. Chrvsotile occurs ii "When fiherized into a ticallv white, unless gray or yellowish gnu fibe'rized'. Crocidolite when the fibers are gray, greenish gray, unless staining ihipur: is silky or pearly. Cirkel stnm- ^ of 2.000 to no visible elb-.-c ...i when chrysoriic- is lies lization is driven off lire, and amosite con higher temperatures t though having a lov magnetic mass. Asbestos does not ! insulation is due to structure, which ada nonconductors of hey * Merrill. G. T\. Proceedir. 2$2-2s`.4!. *Ch'kM. Frit?.. <'hrrsotile Canada I<pt. Mines 1 `Cirkel. Fritz. Work cited. *Danu. I*. S.. Syrota of M ASARCO ALV 0006248 ASBESTOS s for spinning. The bulk of the world 1 short fibers is of this variety. s beh'nir to the amphibole group of min us: 1 -omposition (Fe3Ig)Si0j. is the Onitor States. Usually, it is brittle and is more resistant to the action of acids It is used for nonspinning purposes, a-rich anchophyllite occurring in Africa. The best-grade material is used for -blue asbestos",. having the composition s in commercial quantities chiefly in th spinning and nonspinning purposes, rnrtz is sola as the semiprecious "tiger- j(SiOj)4,_ actinolite, Ca(MgFe),{SiOj),, silicate similar in composition to actinod as the minerals to which the term ually. Except for Italian tremolite, they i. Mountain leather and mountain cork insisting of flexible sheets of interlaced a compact fibrous mass of amphibole last three varieties are mineral euriosicies ie. ICAI PROPERTIES line CHARACTERISTICS roperties of asbestos--those that give it jus structure and fire resistance. The tave qualities possessed by no other minin into yarn or thread, woven into cloth, kings in almost the same way as animal mlil otron or wool, they" consist of 101JS CHARACTER fibrous, the quality of the fiber in the nt deposits is quite diverse. Chrysotile. ually possess high tensile strength, flexi le qualities vary greatly in material from file occasionally is harsh and somewhat o be stronger than clirysotile. The fibers long. Anthophyllite is generally brittle . -although the fiber from some "deposits .d toughness. _ This type usually is more te or actinolite. Tremolite is generally xtile use; Italian tremolite, however, is nt in asbestos strong and flexible enough The fiber is graded on the basis of -ntieal quality may range in price from o length. r PHYSICAL PROPERTIES 3 euteness or eiber Fineness of fiber is measured by the degree of separation accom plished by fiberizing processes. The fibrous structure of asbestos is due to a highly developed prismatic cleavage, the spacings between cleavage planes being infinitesimal or, at least, measurable by the =ize of the ultimate particle of fiber, which is incalculably small. Subdivision, therefore, theoretically may be continued almost inclefinitelv, the fineness that can be attained depending on the delicacy of the tools used and the skill of manipulation. Varieties of asbestos and occurrences of the same variety vary markedly in the ease with which they can be fiberized. Some types can be separated readily into slender fibers, while others are divided Trith difficulty and therefore appear as coarse-fibered material. Mer rill has measured anthophyllite fibers down to 0.002 mm in diam eter.3 and the smallest measured diameter recorded by Cirkel is 0.00075 mm.* Apart from strength and flexibility, the quality of asbestos is measured to some extent by the fineness of fiber attain able and by the amount of processing required to reduce it to the fineness desired. COIOR AND DUSTER Chrysotile occurs in various shades of green or yellowish green. When fiberized into a Suffy mass, all types of chrysotile are prac tically white, unless stained by impurities. Amosite ranges from urav or yellowish gray to white and. if relatively pure, is white when fiberized. Crocidolite is lavender blue, and this color is maintained when the fibers are separated. Anthophyllite and tremolite are gray, greenish gray, or white, and the separated fibers are white unless staining impurities are present. The luster of asbestos usually is silky or pearly. HEAT RESISTANCE Cirkel states that Canadian chrysotile withstands temperatures of 2,000 to 3.000 F. and that a temperature of 5.000 F. produces no visible effect on some varieties.3 It has been found, however, that when chrysotile is heated to a high temperature its water of crystal lization is driven off and it becomes brittle. Anthophyllite, tremo lite. and amosite contain low percentages of water and withstand higher temperatures than other varieties. However, crocidolite. al though having a low water content, is easily fused into a black magnetic mass. HEAT CONDUCTIVITY Asbestos does not have low heat conductivity. Its value for heat insulation is due to its noninflammability ancl also to its fibrous structure, which adapt it for manufacture into coverings that are nonconductors of heat because of their porous nature. 2S12"Me$3rr.ill. G. P.. Procee' dings of the United States National Museum: Vol. 18. 1S05. nn. `Cirkel, Fritz, Chrysotile Asbestos--rts Occurrence. Exploitation. ItUUng. and Uses: Canada Dept. Mines. Mines Branch 69, 2d ed.. 1910. p. $5. * Cirkel. Frit2. Work cited, p. 30. f Dana. E. S., System of Mineralogy: Sixth ed., York. 1911, p. 671. ASARCO ALV 0006249 4 ASBESTOS ACID RESISTANCE Tremolite and anthophyllite are highly resistant to acids. It is claimed that crocidoiite resists chemicals'and sea water remarkably well. Chrvsotile is affected more readily by acids and other chem icals than are the ampliibole varieties. EIECTRICAL RESISTANCE Varieties of chrvsotile lowest in iron content are the most suit able for electrical' insulation. Arizona chrvsotile is superior for this use. Apparently the iron content of amphibole does not affect its use for this purpose because crocidoiite, which upon analysis shows a content of about 35 percent FeO, has high electrical resist ance. This seeming contradiction may be explained by the fact that iron is present m crocidoiite as a silicate, whereas in chrvsotile it commonly appears as iron oxide impurities. SPECIFIC GRAVITY The specific gravity of chrysotile, as given bv Dana.'' is 2.22, but that of the commercial fiber is always higher because of the pres ence of impurities. Canadian chrvsotile ranges from 2.54 to 2.59. and the Arizona fiber, being lower in iron, has a specific gravity of 2.4T. Anthophyllite ranges from 3.1 to 3.2 and crocidoiite is still heavier, ranging from 3.2 to 3.3. CHEMICAL COMPOSITION The chemical formulas for the various kinds of asbestos are given in the section on varieties. Theoretical composition, as calculated from chemical formulas, rarely corresponds with actual composition because more or less impurity is always present. The following table shows analyses of representative commercial fibers. .Inalt/ses of representative asbestos samples, percent SiOi Al:Oj FiOi FeO MgO C0 NajO HjO Total Cbrysotile: Canada ...................... Arizona *...................... Barberton *.................... Sbabani*........................ Russia7.......................... Anthophyllite: Georgia *... Crocidoiite: Capo Colony7. Amosne: Penge *................. Tremolite: Natal......... 40.36 41.66 40.06 40.96 39.2S 56.40 51.10 49.72 5S,80 0.21 1.27 1.90 1.70 1.75 1.15 5.72 * 5.32 1.35 1.60 .40 ............. 0.66 .64 .40 2.44 5.37 11.40 35. SO 37.00 43.86 42.05 38.35 38.73 40.06 2S.6S 2.30 3.77 22.75 6.15 1.74 .50 1.65 10.65 `0.40 MO 6.90 13.45 14.31 16.60 16.07 XL 52 1.63 3.90 2.29 .50 99.89 99.83 99.70 100.00 l0Q.il 99.76 100.00 100.15 98.02 7 Ross. J. G., Chrysotile Asbestos in Canada: Canada Dept. Mines. Mines Branch 707, 1931, p. 20. 7 Dilier, J. S., Mineral Resources of the United States. 1919. Pt. 2. p. 302. 7 Hall, A. L., Asbestos in the Union of Sontb Africa: Union of South Africa Geol. Surrey Mem. 12,191S, p. 31. * Includes KjO. 1 Hu Keyser, Walter A. Chrysotile Asbestos In the Bajenova District, U. S. S. R.: Eng. and Min. Jour., vol. 134. no. 8. August 1933, p. 338. 7 Hopkins, 0. B. Asbestos, Talc* and Soapstone Deposits of Georgia: Geol. Survey of Georgia Bull. 29* 1914. p. 79. 7 Hall. A. L., Work cited, p. 19. * Hall. A. L., Work cited, p. 22. * Hall. A. L.. Work cited, p. 23. 77 Includes FeiO*. xxzmp-- 't&mt SYNTH Varieties of amphibole asbe.* bined chemically as aa essen may be present in any the* form of an oxide th, ] iron impurity in Arizona db Canadian, African, or Russia* Various attempts have been to natural asbestos. Produer slag wool, and fflass trool asbestos but lack its fiexiblitT wool made in 1936 and later with that of asberstloosinyaanrdf arej EA3 The peculiar proper; v of ir structure attracted attention Small amounts were used by serve the ashes of the dead w mortal linen" was so difficul guished patricians and king: A specimen of cremation do in a Roman sarcophagus an Vatican. According to tradii wove asbestos into mats. In lamp wicks and to protec' 't The word "asbestos", t .1 minWal now known by that 1 both ancient and modern. Gr word "asbestos" means "inextconveying quite the opposite acteristic feature of asbestos, reference to the "perpetual" : Virgins. "Lithos amiantos", for asbestos, meant a rock i doubtless referred to the cle; into the fire. Another common name apj because a well-known sourt Karystos, southern Euboea. Strabo referred to stone fn 1 Some of the historical data on tb of articles on the history of the asb* August, October, and November 1935 magazine Asbestos. ASARCO ALV 0006250 ASBESTOS ACID BESISTA1TCB >re highly resistant to acids. It is esis lemicals and sea water remarkably ed more readily by acids and other chemole varieties. CTSICAI BESISTANCE lowest in iron content are. the most suittion. Arizona chrysotile is superior for iron content of amphibole does not affect because crocidolite, which upon analysis 35 percent FeO, has high electrical resist-ramction may be explained by the fact cidolite as a silicate, whereas in chrysotile on oxide impurities. rPECEFIC GRAVITY chrysotile, as given bv Dana,* is 2.22, but oer is always higher because of the presdian chrysotile ranges from 2.51 to 2.59. lg lower in iron, has a specific gravity of ;s from 3.1 to 3.2 and crocidolite is still to 3.3. IICAI COMPOSITION or the various kinds of asbestos are given . Theoretical composition, as calculated irely corresponds with actual composition urity is aiways present. The following iresentative commercial fibers. sen. tshesfoa samples, percent AljOj Te.Oi FeO MgO Ca.0 XajO EiO Total 0.21 1.27 ....1..3.5.. 0.66 L90 :.4o .40 1.70 2.44 __1.73 1.15 . 40 5.37 11.40 _5.72 ______ 35. SO 37.00 . * 5.32 i ...... 43.86 42.05 38.35 38.73 40.05 28.68 2.30 3.77 2175 . 0.15 1.71 .30 1.65 10.65 0.40 .10 13.45 14.31 16.60 16.07 11.52 1.63 2.29 .50 99.89 99.83 99,70 100.00 100. U 99.76 100.15 98.02 nada: Canada Dept. Mines. Mines Branch 707, 1031, p. 20. United States. 1919. Pt. 2, p. 302. :outb -Uricai Union of South Africa Geol. Surrey Mem. 12,1918, xstoa la the Bajenova. District, U. S. S. R.: Eng. and Min. Jour., capstone Deposits ot Georgia: Geol. Surrey of Georgia Bull. 29, SYNTHETIC ASBESTOS 5 Varieties of amphibole asbestos, except tremolite, contain iron com bined chemically as an essential constituent of the mineral. Iron may be present in any variety of asbestos as an impurity, chiefly in the form of an oxide that may be detrimental for some uses. The iron impurity in Arizona fiber is considerably lower than that of Canadian, African, or Russian chrysotile. SYNTHETIC ASBESTOS Various attempts have been made to manufacture a product similar to. natural asbestos. Products known as mineral wool, rock wool, slag wool, and glass wool have some of the properties of chrysotile asbestos but lack its flexiblity and strength. Special forms of glass wool made in 1936 and later are said to have flexibility comparable with that of asbestos and.are capable of being woven and spun. A German inventor claimed in 1932 that he had made an artificial prod uct of the same composition and physical properties as Canadian chrysotile and at a cost lower than asbestos mining costs in Canada. HISTORYr EAEIY BECOEDS The peculiar property of incombustibility combined with a fibrous structure attracted attention to asbestos more than 2,000 years ago. Small amounts were used by the Romans for winding sheets to pre serve the ashes of the dead when bodies were cremated, but the "im mortal linen" was so difficult to weave that only the most distin guished patricians and kings were honored with asbestos shrouds. A specimen of cremation cloth containing ashes was found in 1702 in a Roman sarcophagus and was deposited in the library of the Vatican. According to tradition, the ancient Chinese and Egyptians wove asbestos into mats. In ancient temples, asbestos was used for lamp wicks and to protect altar fires. The word "asbestos", evidently first applied by Pliny to the fibrous mineral now known bv that name, was employed erroneously, for in both ancient and modern Greek it refers to c[uicklime. The Greek word "asbestos" means "inextinguishable" or "unquenchable"--words conveying quite the opposite meaning from "incombustible", a char acteristic feature of asbestos. Possiblv Pliny had in mind Plutarch's reference to the "perpetual" asbestos lamp wicks .used by the Vestal Virgins. "Lithos amiantos", the original term used by the Greeks for asbestos, meant a rock unstained, untainted, or undetiled. and doubtless referred to the cleansing of asbestos cloth by throwing it into the fire. Another common name applied to asbestos was "Karystios lithos" because a well-known source of flexible mineral fiber was near Karystos, southern Euboea. Greece. Early in the first century, Strabo referred to stone from tliis locality that was carded and : Some of the historical data on thla and following pages was obtained from a series of articles on the history of the asbestos-manufacturing Industry that appeared In the august. October, and November 1935 and January, May, and August 193d Issues uf the magazine asbestos. ASARCO ALV 0006251 asbestos 6 woven into handkerchiefs. Solinus and Plutarch also mention a fibrous mineral from this place. These ancient writers evidently I-I.ew little of the deposits, but- as two exposures of serpentine occur oVt of Ivarvstos the fiber probably was chrysotile.6 ' J'uusaiiius. who lived in the second century A. D., refers to incom bustible "Karpasian flax." Some writers think this term indicates that, the source of the fiber was Karpasos. northeastern Cyprus, butno asbestos-bearing rock is known in that vicinity. Evans points out that the word "Karpasos" means <:cotton': and"that probably it was applied to the mineral because of its adaptability to textile use. Cyprus, however, was a well-known source of supply of asbestos in ancient times. Although it is difficult- to determine from early refer ences the exact location of the deposit, probably it was southeast of Mount Troodos in a village known as Amianto, the identity of which is lost. During recent- years chrysotile asbestos has been produced in considerable quantities near a town now known as Amiandos. This is probably the site of ancient Amianto. for it is situated near Mount Troodos. IS miles from the seaport Limasol. William Lithgow, a Scotsman, writing about- the minerals of Cyprus early in the seven teenth ceiitury. referred to "the admirable'stone Amiante. whereof they make Linnen cloth that will not burn, being cast into the fire, but' serveth to make it neat and white." The asbestos used by the Homans doubtless was a long-fibered variety identified as tremolite and occurring in northern ItaTy. The use of Italian fiber presumably led to the claim widely made in litera ture that the original "amiantos" consisted of fibrous amphibole (tremolite, actinolite. or hornblende 1. A recent letter to the author from the chief mineral inspector in Rome, however, casts some doubt as to whether all Italian liber vised by the ancients was tremolite. A significant excernt from this .communication reads as follows: For a long time it was believed that the Italian "amianti" were all the tremolite type because the first examinations of the material were based on samples of tremolite. It was only in recent years that, after further studies, the producers recognized that their products were for the most part chrysotile with a long, flexible fiber. A tremolite asbestos glove examined by the writer in the Museum of Natural History. London. England, in 1935 did not appear to consist of strong fiber. A piece of so-called "asbestos" cloth of un known origin in this museum is not a fabric: it is a felted sheet that may be a natural mountain leather. Yerv little mention of asbestos was made throughout the Middle Ages.' According to report, Charlemagne, who reigned from 768 to S14, had an asbestos tablecloth, which ne would throw into the fire for cleansing. To mystify his guests was apparently the only reason for its use. Marco Polo refers to "amiantos" cloth shown to him during his travels through Siberia in 1250. He was told by the superstitious people of that region that it was made of the skin of salamanders, but ne was too scientifically minded to accept such statements. After much questioning and search, he learned how the fibers were obtained* * Evans. John W., The Identity of the Anri&ntoB or Karystian Stone of the Ancients with Chrysotilet Mineral. Map. (London), voL 14. May 1906. pp. 146-48. Evans, John W.t Work cited, p. 143. and prepared. His desc consisted of potmdimr i- that the fiber was < ; the facr- that- the l. .-1 curring at Minnisinck i Further evidence that may have- applied to ch the' uses of the materia for lamp wicks, practic; Asbestos was woven int and similar fabrics. M and brittle and cannot ' aside from the tremolit South Africa--yarietie; Chrysotile, on the othei adapted for textiles. J it seems reasonable to o in the manufacture of i The next important meeting of the Royal S kerchief of `-salamandi napkin belonging to Fe Asbestos was discove 1710 and 1720. and the f operated during the rei; and handbags were ma EISTOtf The utilization of as ginning in Italy. Abo studies and exporimen the manufacture < t ity. Several coni, .it serious problems were and heat-insulating be. devising suitable mad Exhibits at the Unive publicity to the prodiu In 1860 asbestos was and a specimen of fin in London in 1562. T to work them proficab' began with the discovr ford Mines and Coleri produced in that year. Italian asbestos, and easy availability of a rapid development. of 1.400 tons a year wi sold for only $80 a tovanced to $300 a ton. wasteful and costly h ASARCO ALV 0006252 ASBESTOS fs. Solinus and Plutarch also mention a us place. These ancient writers evidently ts, b' ' as two exposures of serpentine occur r pr --ily was chrysotile.* n the second century A. D., refers to incom- Some writers think this term indicates r was Ivarpasos, northeastern Cyprus, but is known in that vicinity. Evans points lasos" means "cotton" and* that probably it a.1 because of its adaptability to textile use.9 well-known source of supply of asbestos in. . it is difficult to determine from early referf the deposit, probably it was southeast of ge known as Amianto, the identity of which ars chrysotile asbestos has been produced in. ;ar a town now known as Amiandos. This dent Amianto, for it is situated near Mount the seaport Limasol. "William Lithgow, a the minerals of Cyprus early in the sevento "the admirable stone Amiante, whereof that will not burn, being cast into the fire, at and white." the Romans doubtless was a long-fibered olite and occurring in northern Italy. The .lably led to the claim widely made in literaamiantos" consisted of fibrous amphibole hornblende). A recent letter to the author spector in Rome, however, casts some doubt .iber used by the ancients was tremolite. A this communication reads as follows: Sieved rim tlie Italian "amlanti" were all the .'rst examinations of the material were based on ? only in recent years that, after further studies. : tliet. utluers were for the most part chrysotile ove examined by the writer in the Museum don, England, in 1935 did not appear to 1 piece of so-called "asbestos" cloth of uneum is not a fabric: it is a felted sheet that in leather. asbestos was made throughout the Middle >rt, Charlemagne, who reigned from 768 to icloth. whichlie would throw into the fire y his guests was apparently the only reason amiantos" cloth shown to him during his n 1250. He was told by the superstitious t it was made of the skin of salamanders, y minded to accept such statements. After :cli, he learned how the fibers were obtained r of the Amianros or Karysrlan Stone of the Andeats London voi. 14. May 1900. pp. 14;i-48. p. 14*. HISTORY 7 and prepared. His description of the process of preparation, which consisted of pounding in a mortar to eliminate impurities, suggests that the fiber was chrysotile, and this conclusion is substantiated by the fact that the best-known asbestos of Siberia is chrysotile oc curring at Minuisinck near the Mongolian border. Further evidence that the term "amiantos" as used bv the ancients mav have applied to chrysotile as well as to amphibole is found in the" uses of the material. With the exception of twisted fiber used for lamp wicks, practically all the early references are to textile use. Asbestos was woven into handkerchiefs, tablecloths, winding sheets, and similar fabrics. Most varieties of amphibole asbestos are weak and brittle and cannot be spun or woven. The principal exceptions, aside from the tremolite of Italy, are the crociaolite and amosite of South Africa--varieties unknown until comparatively recent years. Chrysotile, on the other hand, is strong, flexible. and silky and welladapted for textiles. Judging from the probable sources of supply it seems reasonable to conclude that it was employed in ancient times in the manufacture of incombustible fabrics. The next important reference to asbestos was in 1676 when, at a meeting of the Royal Society, a Chinese merchant exhibited a hand kerchief of "salamander's wool" or "linum asbesti." _ An asbestos napkin belonging to Ferdinand III was exhibited in Vienna in 1679. Asbestos was discovered in the Ural Mountains of Russia between 1710 and 1720. and the first factory for making asbestos products was operated during the reign of Peter the Great." Textiles, socks, gloves, and handbags were made here for 50 or 60 years, but the enterprise failed, through lack of demand and poor transportation facilities. HISTORY OF COMMEECIAZ PRODUCTION The utilization of asbestos on a commercial scale had its real be ginning in Italy. About 1808, a noblewoman of Valtellina sponsored studies" and experiments that brought her mauy honors and led to the manufacture of asbestos thread"fabrics, and paper of high qual ity. Several companies were-formed between 1860 and 1875. h'o serious problems were involved in the manufacture of rope packings and heat-insulating board, but much difficulty was encountered In devising suitable machinery for the fabrication of spun products. Exhibits at the Universal "Exposition in Paris in 1878' gave wider publicity to the products then manufactured. In I860 asbestos was discovered near St. Joseph in Quebec. Canada, and a specimen of fine silky fiber from this region was exhibited in London in 1862. The deposits were few and small, and attempts to work them profitably failed. A new era in the asbestos industry began with the* discovery, in 1877. of the famous deposits near Thetford Mines and Coleraine. Mining began in 1878 and 50 tons were produced in that year. The fiber could be worked more easily than Italian asbestos, and its popularity in London, together with the easy availability of a growing market in the United States, led to rap'id development. Seven quarries with an aggregate production of 1.400 tons a year were reported in 1S85. The nighest-grade fiber sold for only 880 a ton in that year, but by 1900 the price had ad vanced to $300 a ton. Thereafter, owing to depressed prices and to wasteful and costly hand methods of mining and preparation, the ASARCO ALV 0006253 ASBESTOS 10 the coloring of shingles has attained higher refinement. recen1/*0.cemet s;ding shingles have been developed. Flat sheet forsidin"' and roofs came into use shortly after 1903. and corin,f -ed sheeting was first made in 1905. Production of this great n-uiip of building materials has attained large proportions during Se past 15 or 20 years. Asbestos-cement pipes were first manufactured at Genoa. Italy, in 1913 by the Eternit process. Their manufacture began in America in 1929 and the first shipment was made in 1930. 0RIGE? Asbestos originates for the most part from rocks consisting largely of olivine, such as peridotite or dunite. or from pyroxenite. Most chrvsotile deposits result from alteration of olivine to serpentine, with subsequent prismatic crystallization providing the fibrous struc ture. Contact as well as regional metamorphism evidently plays an important part in the process because in various regions, notably the Canadian and Khodesian fields, intrusive rocks are associated with the deposits and doubtless definitely influenced their development. Prismatic crystallization occurs in fractures. More detailed discus sions of origin will be found in later sections describing asbestos deposits by State and country. Chrvsotile occurs in two forms--cross fiber and slip fiber. The former is the characteristic occurrence in all fissure-filled veins, the fibers crossing the veins approximately at right angles to the walls. In some veins the fibers cross from wall to wall, hence the fiber length is governed by the width of the vein. In others the fibers may be broken into two or more lengths by partings parallel with the Vein walls. Slip fiber, on the other hand, parallels the vein wall and usually shows the effects of pressure and movement along a fault plane. Figure 1 shows typical cross-fiber veins of Canadian asbestos. The chrvsotile occurring in sedimentary _ rocks in Arizona and in the Carolina district of the Transvaal originated in a quite dif ferent way. The fiber in these localities is regarded as a product of alteration of magnesian limestone metamorphosed by diabase in trusions. It occurs m cross-fiber veins. Under some conditions peridotites and pyroxenites are altered to fibrous amphiboles, of which the most common is anthophyllite. In some places it occurs as slip fiber in shear zones, but more commonly the altered rock takes the form of pockets or lenses consisting almost entirely of irregularly arranged bundles of fiber. The rock is called amphibolite, and the asbestos is of the mass-fiber type. In the ir regular belt of olivine- and pyroxene-bearing rocks that extends from the Gaspe Peninsula in Canada to southern Georgia the alteration was principally into massive serpentine and chrvsotile in the north ern part, tnat is, in the area lying in Quebec, Canada, and in Ver mont; but in its southern extension only sporadic occurrences of chrvsotile are found because the alteration was more generally to anthophyllite and talc. The softest and most easily fiberized anthophyllite occurs generally near the surface of the_ deposits; with increasing depth the fiber be comes harsher, more brittle, and less easily worked into a fluffy mass. The development of the best fiber therefore appears to depend upon 'l I ASARCO ALV 0006254 ui!|pttun,) jo ptipA jyju-soJ3 p M p I.fj,--*i aurtiiQ t ASBESTOS shingles "has attained higher refinement, hingles have been developed. Flat shee me/' *o use shortly after mat' ' n" 1905. Production of th^ great s has attained large proportions during re first manufactured at Genoa, Italy. " 5. Their manufacture began in America nt was made in 1930. OSIGHJ e most part from rocks consisting largely te or dunite, or from pyroxeiute. Most rom alteration of olivine to serpento, rystallization providing the fibrous stiuc"ional metamorphism evidently plays an Is because in various regions, notably tne elds, intrusive rocks are associated witn definitely influenced their development, curs in fractures. More detailed discusnd in later sections describing asbestos 7fo- rms--cross fiber and slip fiber. The occurrence in all fissure-filled veins, the roximately at right angles to the walls, from wall to wall, hence the fiber length the vein. In others the fibers may be irths by partings parallel with the vein her hand, parallels the vein wall and pressure and movement along a fault I cross-fiber veins of Canadian asbestos, in sedimentary rocks in Arizona and te T'-onsvaal originated in a quite difese alities is regarded as a product mesume metamorphosed by diabase inber veins. idotites and pyrosenites are altered to the most common is anthophyllite. In ber in shear zones, but more commonly n of pockets or lenses consisting almost ed bundles of fiber. The rock is called ; is of the mass-fiber type. In the irroxene-bearing rocks that extends from da to southern Georgia the alteration serpentine and chrysotile in the northlying in Quebec, Canada, and in Verrtension only sporadic occurrences of the alteration was more generally to iberized anthopbyllite occurs generally ts; with increasing depth the fiber he ld less easily worked into a fluffy mass, iber therefore appears to depend upon ASARCO ALV 0006255 USES 11 t-he action of weathering agencies. Consequently, deposits of soft, easily worked anthophyllite tend to take the form of pockets or lenses of limited depth, and if workings are to be confined to fiber of this character the limitation of reserves must be considered with care, rf however, the harsher, more solid asbestos masses can be fiberized successfully, into marketable products, the reserves may be much more extensive. Most of the deposits that have been developed show little promise of large reserves. The crocidolite and amosite of South Africa originated from rocksquite distinct from peridotite or pyroxenite. They were derived j-rom sediments rich m iron and silica, known as banded iron stones, prismatic crystallization in cross-fiber veins probably was assisted to some extent oy contact metamorphism. MODE OP OCCTJEEENCE From the discussion of origin, it is evident that there are three types of asbestos deposits--cross fiber, slip fiber, and mass fiber. Cross-fiber asbestos consists of innumerable strands extending across veins from wall to wall, except where interrupted by longitudinal seams. Most commercial deposits of chrysotile, amosite. and croci dolite are of this type, but anthophyllite rarely, if ever, occurs in cross-fiber veins. In slip-fiber deposits the strands more or less par allel the vein walls. They frequently show slickensided surfaces because they occupy shear zones where the rock has been subjected to movement and pressure. Slip fiber is common in the chrvsotile deposits near Eden, Vt., and predominates in the anthophyllite de posits at Pvlesville, Md., and near Bedford and Rocky Mount. Va. In mass-fiber deposits there is no definite orientation of fibers. Almost the entire mass of the rock is. composed of bundles of fibers or needles that sometimes show a radiating structure. This type of occurrence is confined almost exclusively to the anthophyllite variety and is well-exemplified by deposits at Sail Mountain, Ga., and Kamiah, Idaho. USES The uses of asbestos are so numerous and important that one coulcl write a book on that subject alone. On the basis of use, asbestos falls into two principal classes--spinning and nonspinning fiber. Spinning fiber comprises the longer grades of chrysotile, crocidolite. amosite, and, exceptionally, tremolite. Nonspinning fiber comprises the shorter grades of these varieties and both the long and short grades of anthophyllite and related amphibole varieties. Spinning asbestos is used for weaving into textiles, but under the general classification of textile uses are included prepared yarns, listing, tape, rope, cord, wick, and thread. The largest use of asbestos tex tiles is for the manufacture of automobile Drake-band linings and clutch facings. As much as 70,000,000 linear feet of brake-band lin ing has been made in a single year in the United States. Asbestos cloth treated with rubber is made into gaskets for use between the abutting or flange ends of pipes, or between adjoining surfaces, such as manhole and handhole plates, to make the joints tight enough to prevent passage of air, steam, or oil. Asbestos cloth is used.ltlso, for the manufacture of fireproof theater curtains and scenery'; blauk- ASARCO ALV 0006256 12 ASBESTOS ets: mattresses: firemen's suits, gloves, and shoes; aprons: mittens; laggings: helmets: awnings: conveyor belts for carrying hot mate rials: and woven sheet-packings, braided and twiste"d packings are closely related to textiles. An'important use for nonspinning asbestos is for compressed pack ings consisting of felted masses of fiber combined with rubber or other binders." They are of various forms known as compressed sheet, coil, spiral, and high-pressure packings. Another large group of uses is for heat insulation: in fact, as bestos is one of the most important fireproofing and heat-insulating materials known. Among the best-known products is 85-percent magnesia pipe covering. Asbestos paper is used for making 3-ply air-cell and similar pipe covering; as sheeting between floors; lining for stoves, heaters, filing cabinets, soldiers' helmets, mufflers for auto mobiles, drum controllers in sulphite mills, automobile radiator cov ers; tubes for electric wires; table mats, pads, stove mats, and other household appliances; and in many other ways. Asbestos paper is also used extensively in the manufacture of asbestos felt roofing and built-up roofs and in making' asbestos-protected metal roofing. Millboard is used not only as a building material but as a joint packing for steam pipes and as a lining for safes, stoves, electric switch boxes, hoods of automobiles, and ovens, where' a material of greater thick ness than paper is required. An important use of millboard is for gaskets on automobiles and steam machinery. Asbestos is used for Jagging steam boilers to prevent heat radiation. Large quantities of the shorter fibers are used in plastic fireproof cements for boiler, pipe, and furnace, covering. An asbestos-cement coating is sometimes ap plied to the surface of wallboard for both heat insulation and fire proofing. Numerous household appliances, such as pot holders, mats, and table covers, may be classed in the group of heat-insulating materials. Large quantities of the shorter grades of asbestos are used in the manufacture of building materials. Roofing shingles made of portland cement and asbestos are used extensively. Compressed sneets of asbestos combined with cement are used for corrugated sheeting, wallboard, millboard, lumber, and floor tile. Corrugated asbestos sheets have special meric in constructing chemical plants or other buildings exposed to a corrosive atmosphere. Asbestos-cement wall tiles in a wide range of colors were introduced about 1930. Asbestoscement products are used increasingly in Europe sis roofing, ceilings, partitions, paneling, linings of ihte'rior and exterior walls, water pipes, and gutters. It is claimed that the pipes and gutters are waterproof, require no painting, and compare favorably in strength with cast iron. It has been found that wooden flooring may" be nailed to a subflooring consisting of concrete to which about 10'percent of asbestos has been added. Asbestos-composition products are becoming popular for floor tile in homes and on ships. Miscellaneous uses are innumerable and diverse. There is a marked tendency toward a more extensive use of molded brake bands in automobiles. Of the brake bands made in 1929, about 84 percent were woven and 16 percent molded. In 1931, 70 percent were woven and 30 percent molded, and in 1933 these percentages were, respec tively, 59 and 41. This trend indicates a relatively wider use of non spinning asbestos at the expense of spinning grades. However, in 1935 there was a slight reve and 39 percent molded, ksbestos-cement pipp- -t mains and sewere 1 relatively nonconductive of so elastic that traffic vibrati over, they' are easily placet vancageous for carrying so rust. A standard Europea 20 percent asbestos. ~ Asbestos is used in firepr the surface of metal sheeti ings, for covering fire hose A"process has been perfect steel by means of metall; process"will promote wider Asbestos paper and mil Short-fiber asbestos mixed asphalt improves the surf; Asbestos is used as a pc suitable for common scour imparting a high luster. In the chemical laborat stoppings hi combustion ti and for wicks which wher produce colored flames. , are combined with the fit cloth of greater strength, a forcenient perntits the use as iron. Monel, nickel, and choice dependhur on the operating conditions. Asbestos is used as a fil articles in which a V i besros compounds arc The uses of nnthophy strength. It- is too weak i for asbestos-cement siting! strength of the fiber imp of its"superior resistance t laboratories. The strong tough slip fiber oceurrint the most suitable for Rite: Italian tremolite is also u.may be employed for oth previous paragraph. The principal uses kno- cements to cover boilers, ] battery boxes, and as an acoustical and other wall for mineral wool in ho; consistent market for it 1 -....... - .1 1 ... 'I ! ASARCO ALV 0006257 ASBESTOS ? suits, gloves, and shoes^ apron 'ho(.'mate_ Igi^'^ded Jd twisted packings are wSb? fbberStcombfnedC vitl? rubber or various forms known as compressed Tygeifis^for heat insulation; in fact, as- inportanc fireproofing and heat-insulating r the best-known products is 85-percent Asbestos paper is used for making 3-ply vering; as sheeting between floors; lining binets, soldiers' helmets, mufflers for autoa sulphite mills, automobile radiator eov; table mats, pads, stove mats, and other in many other ways. Asbestos paper is manufacture of asbestos felt roofing and g asbestos-protected metal roofing. 'Millbuilding material but as a joint packing ng for safes, stoves, electric switch boxes, veils, where a material of greater thick- An important use of millboard is for steam machinery. Asbestos is used for rent heat radiation. Large quantities of plastic fireproof cements lor boiler, pipe, isbestos-eement coating is sometimes apboard for both heat insulation and firerid appliances, such as pot holders, mats, lassed in the group of heat-insulating orter grades of asbestos are used in the aerials. Roofing shingles made of porte extensively. Compressed sheets me^B:e used for corrugated sheeting, r, a^r floor tile. Corrugated asbestos constructing chemical plants or other -five atmosphere. Asbestos-cement wall were introduced about 1930. Asbestoseasmgly in Europe as roofing, ceilings, of interior and exterior walls, wafer limed that the pipes and gutters are ns, and compare favorably in strength found that wooden flooring may be ing of concrete to which about 10'per;d. Asbestos-composition products are i in homes and on ships, numerable and diverse. There is a re extensive use of molded brake bands bands made in 1929, about 84 percent Ided. In 1931, 70 percent were woven a 1933 these percentages were- respecindicates a relatively wider use of nonase of spinning grades. However, in USES 13 1935 there was a slight reversal of the trend, 61 percent being woven and 39 percent molded. Asbestos-cement pipes are being used increasingly for water and ,,as mains and sewers. They are resistant to acids, noncorrosive, relatively nonconductive of heat and electricity, light in weight, and so elastic that traffic vibrations are unlikely to cause leakage. More over, they are easily placed and joined. They are particularly ad vantageous for carrying solutions that must be kept free from iron rust. A standard European pipe consists of 80 percent cement and 20 percent asbestos. Asbestos is used in fireproof paints, in arc welding, for protecting the surface of metal sheeting, as a constituent of asphalt roof coat ings, for covering fire hose, and in the manufacture of gas burners. A process has been perfected whereby asbestos may be cemented to steel by means of metallic adhesives. Commercialization of this process will promote wider use of asbestos-protected metals. Asbestos paper and millboard are used for electrical insulation. Short-fiber asbestos mixed in proportions of 4 to 6 percent with asphalt improves the surface of roads. Asbestos is used as a polishing agent. _ A rough asbestos cloth is suitable for common scouring, and an acid-refined asbestos cloth for imparting a high luster. In the chemical laboratory asbestos is used for acid filters, for stoppings in combustion tubes, for fireproof supports and protectors, and for"wicks which when saturated with various mineral salts will produce colored flames. A filter cloth in which noncorrosive wires are combined with the fiber has an advantage over the all-asbestos cloth of greater strength, and also of lower cost because the wire rein forcement permits the use of lower grades of asbestos. Metals such as iron. Monel, nickel, and lead-coated steel are used for the'wires, the choice depending on the nature of the solution to be filtered, and operating conditions. Asbestos is used as a filler in'insulators and various other molded articles in which a bituminous binder such as gilsonite is used. As bestos compounds are used to some extent in automobile bodies. The uses of anthophyllite are limited because of its lack of strength. It is too weak for spinning purposes, and it cannot be used for asbestos-cement shingles or other products to which a high tensile strength of rite fiber imparts essential qualities. However, because of its'superior resistance to acids, it is well suited for use in chemical laboratories. The stronger grades are used for chemical filters. A tough slip fiber occurring near Pylesville. Harford County, Md.. is the'most suitable for filter use of any yet found in the United States. Italian tremolite is also used for filters. Anthophyllite and tremolite may be employed for other chemical-laboratory uses mentioned in a previous paragraph. The principal uses known for anthophyllite are for making plastic cements to cover boilers, pipes, and furnaces, as a filler in rubber and battery boxes, and as an admixture in cement and plastic flooring, acoustical and other wall plasters, arid stucco. Its use as a substitute for mineral wool in house insulation is contemplated. Ho large, consistent market for it has yet been developed, and production has never exceeded a few hundred tons a year. 134342*--37----- 2 ASARCO ALV 0006258 14 ASBESTOS Many industries use asbestos in hundreds of minor ways. The catalogs of some asbestos-produet companies contain lists of several hundred articles in which asbestos is a more or less essential ingredient. From the foregoing enumeration of uses, it is apparent that large quantities of asbestos are employed in making brake bands, clutch facings, gaskets, packings. and insulation for'automobiles. There fore.'fluctuations in automobile production are likely to be reflected in the amount of asbestos consumed. A second important field of utilization is for heat insulators, roofing, siding, millboard, wallboard. lumber, paper, and roof coatings, all of winch are used exten sively in the building trades. Asbestos consumption, therefore, is influenced greatly by the volume of building construction. Figure 2 | .L/AutomoMe production j J ^! ^1 1 ! 1 \\ 1 ! 1 1 \ i /I j 1 !11 j Vl^Asoesus consumption | / T1 v\ i ! 1 1 1 i ->\i ! i /i //! 1 i 1 1 k i i / / 1 ___ 1____!____ ___ !____-vM ^1.-1 1 1 1 : v.T .-i 1 1 1 1 1 i \V 1 J Y j j j Quitting construction''"P" "'I''"'"' 1 1 i i ii i i 1 1 1 i 1 i ! -| io'------------------------- :------------ 1------------ :------------:------------ :------------ :------------!------------:------------ 1 2926 1927 - 1928 1929 1930 1931 1932 1933 1934 1933 1936 Floras 2.--Asbestos consumption compared with automobile production and building constructiou. 192G-3G. Unlike unit* are reduced to percentage* of the 1923-20 aver* ace. Statistics of asbestos are fruiu tbe Bureau of automobiles from the U. S. Bureau of the Census, and building contracts from tbe Federal Ke*erve Board. shows the relation that exists between asbestos consumption and these two important industrial activities. The chart indicates that during the depression years 1930 to 1933 asbestos consumption stood at a relatively higher level than either automobile production or building construction. Doubtless, this is due to the fact that during these'years asbestos building materials) were used in considerable quantities for the repair and maintenance of existing buildings and that a substantial volume of brake-band linings and clutch facings was used to recondition old cars and trucks. GENERAL DISTRIBUTION The United States has never attained importance as a producer of asbestos, the domestic output being only 1% to 4 percent of the quantity required to supply raw material for its_ extensive asbestosproduct manufacturing industries. Production is centered in four principal countries--Canada, Rhodesia, Union of South Africa, and PRODUC ,e Soviet Union. Since lercial commodity the P an* produced, but r ' t K is of the shortc < f South Africa and JKh. s sources of the higher Tar. Russia ranked hex; urine the revolutionary imost at a standstill, j acli year since then pro Smaller quantities of : 'inland, and several oth Chrvsotile is the lead nit substantial qtianticie tiso are produced in th< >f anthophvllite and sii i'nited States. Italy, Bu PRODU HISTORY OF F Scattered deposits in nsuisphpeldieda lsimmaitell dqutoanmniatic" fiber has been produced duced principally in A contain considerable reare not favorable for lc and cosily. Arizona h some interruptions sine but furnish shorr fiber intermittently since 19 The followin': r"UT. -- T'nired S:a } Year lSSG.. 1651... 1552... 1653.. 18W1885.. 1S86-. 1887.. 1888.. 1889.. 1690.. 1891.. 1892.. 1893.. 1894.. 1895.. 1896.. 1897.. 1898. Short tons Value : 150 . 200 . 111...200000000 ' 54.312 7,000 36.000 30.000 30.000 300; 9.000 6.000 115000 , 4.500 3.000 30: 1.800 71 ` 4,560 66 . 3,960 10540;; 6.416 2.500 325 4.463 795 ! 13.525 504 : 6.100 580 ' 6.450 i 605 10.300 I ASARCO ALV 0006259 ASBESTOS bestos in hundreds of minor ways. The prod^t companies contain lists or several ch ^Bstos is a more or less essential meratioh of uses, it is apparent that large employed in making brake bunds, clutch . and insulation for~automobilos. Thereiol>iIe production are likely to be reflected : consumed. A second important field of itilators. roofing, siding, millboard, wallroof coatings, all of which are used extendes. Asbestos consumption, therefore, is olume of building construction. Figure 2 "between asbestos consumption and these ivities. uring the depression years 1930 to 1933 it a relatively higher level than either tiding construction. Doubtless, this is tliese~years asbestos building materials xntities for the repair and maintenance at a substantial volume of brake-band vas used to recondition old cars and J, DISTRIBUTION r attained importance as a producer of : being only 1% to 4 percent of the aw material for its extensive asbestositries. Production is centered in four Rhodesia. Union of South Africa, and PRODUCTION AND CONSUilPTION 15 Soviet Union. Since asbestos first became an important comthe .ini commodity the Province of Quebec, Canada, has led in ton1 A t>roduced, but a large proportion of the output of this Prov!ul= if 0f the shorter, nonspinning grades. Since 1916, the Union 11l|.,lth Africa and Rhodesia have pecome increasingly important sources of the higher-grade spinning fibers. Before the World ??. . Russia ranked next to Canada as a producer of asbestos, but lii'rin0- the revolutionary period the industry in that country was C lmost at a standstill. In 1926, however, activity was revived, and ach vear since then production and exports have increased greatly. 6 Smaller quantities of asbestos are produced in Cyprus, Australia, Finland, and several other countries. 1 Chrysotile is the leading product in all the producing countries, but substantial quantities of blue (crocidolite) and amosite asbestos also'are produced in the Union of South Africa. Minor quantities of anthophyllite and similar amphibole varieties are mined in the United States, Italy, Bulgaria, Finland, and several other countries. PRODUCTION AND CONSUMPTION HISTORY or PRODUCTION IN THE UNITED STATES Scattered deposits in California and other Western States fur nished a limited tonnage of asbestos many years ago. Georgia has supplied small quantities of anthophyllite, and the'"same or similar fiber has been produced at times in other States. Chrysotile is pro duced principally in Arizona and Vermont. The Arizona deposits contain considerable reserves of high-grade spinning fiber, bur they are not favorable for low-cost mining, and transportation is difficult and costly. Arizona has produced a small tonnage annually with some interruptions since 1913. The Vermont jlepo'sits are extensive but furnish short fiber almost exclusively. Vermont has produced intermittently since 1908. The following table, compiled from data reported by producers to the United States Geological Survey until 1924 and thereafter to the United States Bureau of Mines, shows the history of production since 1SS0. Asbestos sold iit the United States, 1880-1938 Vear Short tons Value Vear Short tons Value Vear Short tons Value 1880............ 1851............ I5S3............ ISM............. 1885............ 1S86............ 1587............ 1888............ 1SS9........... ISM............ 1891........... 1892............ IS93............ 1894............ 1895............. 1S96............. 1897............. 1398........... 150 200 1,000 1.000 300 200 150 100 30 n 86 m 30 325 795 SM 550 60S $4,312 7.000 30.000 30.000 9,000 6.000 4.300 3.000 1.800 4.560 3.960 6.416 2.500 4.463 13.525 6.100 6.450 10.300 1899............. 1900............. 1901............. 1902............. 1903............. 1904............. 1905............. 1906............. 1907............. 1903............. 1909............. 1910............. 1911............. 1912............. 1913............. 1914............. 1915............. 1916............. 1917............. 681 1.054 747 1.005 $87 1.480 3.109 1.695 653 936 3.085 3.693 7.604 4.403 1.100 1.247 1.731 1.638 1.958 $11,740 16.310 13.498 16,200 16.760 25.740 42.975 23.565 1LS99 19.624 62.603 63.357 U9.935 87,959 11.000 IS. 965 76.952 180.994 291.014 1918............. 1919............. 1920............. 1921............. 1922............. 1923............. 1924............. 1926............. 1927............. 1923............. 1929............. 1930............. 1931............. 1932............. 1933............. 1934............. 1935............. 1936............. 90S 1.161 1.643 531 67 227 300 1.35S 2.961 2.239 3.155 4.242 3.223 3.359 4.745 5.087 3.920 11.012 $U8.687 218.265 673.231 336.968 10.120 9.626 1Z 526 134.731 336. $82 351.178 351.004 2S9.2S4 118.967 105.292 130.677 158.347 292.927 309.994 ASARCO ALV 0006260 ASBESTOS 16 The following table shows sales for a series of years by variety of fiber. For the period 1926 to 1928. inclusive, and. again, suhy quent to 1931. the number of operators reporting was so small th* separation by varieties could not be done without revealing in<j; vidual figures. Ashcslot oM bp producer3 in the United Staten. 1921-31, bit rnrictir. Year Chrysotlle Ampbibole Total Short tons Value Short tons Value Short tons Valu 1921.............................................. 1922.............................................. 1923.............................................. 1924--........................................... 1925.............................................. 1926.............................................. 1927.............................................. 1928.............................................. 3929.............................................. 1930.............................................. 1931.............................................. 4W 25 69 173 93 0) (') (`) 1.953 3.653 2.S57 $313,266 3.320 4.433 33.941 40,750 0) (') (>) 317.584 273.292 111. 70S 393 42 15$ 127 1.165 0) () 0) 3,172 569 37t $23,700 6. $00 5.193 8.585 10.950 (>i 0) (') 33.420 15.992 7.259 S3K 67 300 3.25$ 1.3AS 2.9l 2.239 3.155 - 4.242 3.225 10. 9. 42. 51. 134.' 336. 3JI. 33l.< 289., us. ' Bureau of Miaes not sc liberty to publish figures. WORXD PRODUCTION The following table, compiled by the Foreign Mineral Ferries Division. United States Bureau of Mines, shows production of ashestos b*v countries for 5 *v> ears. World production of asbestos. 1931-3o, in metric tons1 lCompiled by M. T. Latus. Foreign Mineral Serric** Division J Country 1931 1932 1933 1934 1531 'Australia: 8 6 116 149,047 264 3.628 (<> 551 500 10 6 632 1.000 21,810 4 14.221 64.674 2.92S )7 20 112 111,562 250 1.626 (> 756 . 300 9 91 1.2S4 1.000 14,303 5 58 tO. 950 59.800 3,229 13 270 143,667 236 12 4.640 1.200 400 14 3.267 1.000 27,361 120 14.411 71.700 4,305 141.502 290 ton 3ft * 29.224 15.960 92.200 4,615 190.93; 7.634 ftt 61 ` 1.009 35.644 10f 20,683 95,500 8,092 1 In addition to countries listed, Bolivia, Bratil, and Madagascar are reported to produce small quantities of asbestos. * Rail and river shipments. * Exclusive of sand and gravel, production of which Is reported as follows: 1031,6,540 tons: 1933,3,151 tons: 1933.5,850 ions: 1934.4.238 tons; 1935, 2,744 tons. < Data not available. 1 Exports. * Approximate production. These figures include both long and short fibers of all varieties of asbestos. The output in Rhodesia and the Union of South Africa I y ia '! . ASARCO ALV 0006261 ASBESTOS vs sales for a series of years by. varieties 926 to. 1028, inclusive, and, again, subse0f f^^itors reporting was so small that iid J^Pbe done without revealing indi- in the United States, 1921--V, by varieties Amphibole Total Value Short tons Value Short tons Value 313,268 3,320 4,433 33,941 40,750 0) 0) (0 317.584 273.292 112.708 393 42 158 127 1,165 m ') pi 1.172 580 371 523,700 6.800 5.193 8.585 10.950 0) 0) (') 33.420 15.992 7.259 831 67 227 300 1,258 1.353 2.981 2.239 3.155 4.242 3.223 $336,968 10.120 9.526 4Z521 51,700 134.731 336.582 351,173 351.004 2S9.2S4 US. 967 b Szurss. IID PRODUCTION- lpiled by the Foreign Mineral Service ;au of Mines, shows production of asbes- asbestos, 1931-35, in metric tons1 tus. Foroiqn Mineral Service Division] j 1031 1932 1933 1934 ..........1........... _s P 149.047 264 ......... 3. n*>8 f4\ 5*1 500 10 8 432 21. $10 ......... 4 It. 221 44.47< 2.92$ 37 20 112 lU. 562 250 (<) 9 91 1.2S4 1.000 14.303 5 58 10.950 59.800 3.229 13 270 143,667 1.200 14 3.267 1.000 27,381 120 14.411 71.700 4.305 137 141.302 2.100 30 2.252 1,000 29.224 4 15.90 92.200 4*615 1935 143 190.931 rno (*) {*) l.onn 104 20.653 95.500 3,092 null, and Madaeascar are reported to produce small quantities nu.>fwhich is reported as follows: 1931.6.3-10 tens: 1333.3.151 tons: long and short fibers of all varieties of odesia and the Union of South Africa PRODUCTION AND CONSUMPTION 17 ists principally of spinning fiber and the better grades of mill because the local demand is small and the value of the very short fihers too low to justify shipment to foreign markets. Eussia, on fhe other hand, has developed important asbestos-products industries t utilize large quantities of short fiber from the Urals. Canada w small local demand for short fiber, but the industrial centers of the eastern United States provide a ready market, and for this reason the shorter grades constitute a large proportion of the asbestos pro- ^The^utput of most countries reached a low level in 1932 but has shown a rapid increase since, that date. The Kussian industry ex perienced only a minor decline during the depression, and a sub stantial increase in output from year to year since 1932 is indicated. PtacES 3.---Asbestos production in the three leading foreign centers and in the United r* * states, 1916-35. Figure 3 shows production in the three leading foreign centers and in the United States for a 20-year period. Canadian production indicated in the chart does not include the lowest grade product des ignated "sand, gravel, and stone (waste rock onlvjf." For other dis tricts the entire marketed production is included. The minor importance of the United States among world pro ducers, the leading position of Canada, and the. recent rapid gain in prominence of Eussia are apparent. On the basis of value of output, Africa and Russia hold a relativelv stronger position than is indicated on the chart, because Canada produces a preponderance of the lowerpriced short fibers. WORLD CONSUMPTION- It is more difficult to determine the consumption of asbestos than its production. Production plus imports minus exports of raw asbes tos for any year may not give a true picture of consumption, because stocks may be held over for some time and reexported or material consumed may consist of stocks imported in a previous year. The ASARCO ALV 0006262  IS ASBESTOS following table, taken from Asbestos.11 furnishes interesting data on consumption. The figures were compiled by "Tropag" Asoest- und. Erzimport G. m. b. H.. Hamburg. Germany, from data supplied by the ministerial and consular offices of the countries concerned. World cOHxtnnptioi* of axbesto*. 1031-33 (long fnttx) Consumption 1921 ; 1932 1 1933 Consumption 1931 1932 1933 rnltfd Suits................ 121.539 Canada........................... i 4.800 Russia............................ * 40.000 Japan.............................. 7.300 England......................... 19.561 France............................ ` 10.000 Belgium......................... 12.609 Italy................................ 5.134 Spam............................... 3.277 Portugal......................... 56 Netherlands.................. 206 Denmark......'............ 705 Germany........................ 9.808 Austria........................... 5.018 Huneana........................ 2.394 CuchosloTStia............. 4.878 Switzerland............. 1.145 86.311 15,000 `44.000 7.650 17.404 `6.000 5.190 3.791 4.132 160 157 736 7,581 3.466 1.597 7.044 ' 563 106,75* Poland...................... 321 1 6,500 Norway.............. ` 1.000 `45. 00ft Sweden...................... 9.000 Estonia...................... 968 63 24.386 Finland..................... 14. 354 Latvia....................... 62 50 11.239 Lithuania.................. 80 *0.000 . Jugoslavia................. 1.202 6.0*9 N Rumania................... 65 SH Australia................... <300 India....................... | t 750 i Africa--.................... f U.200 12.613 j! South America and 1.267 ` other countries.......... 7$1 0.208 Total, loop tons........ 253.893 832 Total, metric tons... 257,955 342 784 1.193 21 42 35 11 474 65 <400 ` 1.100 205.179 208,462 529 987 * 1.2O0 3628 `35 ` 50 303 * 65 ` 750 ` 7.50 255.095 259.177 < Estimated. The difference in total consumption for 1933. as given in this table (259.177 metric tons), and total world production in that year, as compiled by the United States Bureau of Mines (276.140 metric tons), may'be explained by variations in stocks and materials in transit. The following table presents a compilation of apparent world consumption for 1934 based on production plus imports minus ex ports. Because of variations in stocks, the figures are approximate only. For instance. Canadian consumption as shown in tins table is a negative quantity because, with a steadily increasing market de mand. exports were drawn from stocks as well as from current pro duction. Canadian consumption ranges from 3.000 to 6.000 tons a year. As indicated in the world totals, consumption balances rea sonably well with production-. World rontvmption of asbeston. 103-1 fin metric tons] Asia: Continent and country ! ^ticmU(C* ! I Imports1 584 90 Tnrkev........... ........................ 966 2a 515 1.291 j< 14 Total. Asia...................................................................: 0.035 1 a. <60 Exports * 7.712 96 7.808 Apparent consump tion 874 94 991 21.515 1.195 14 4 24.687 i Complied by Foreign Mineral Service Division. U. 6. Bureau of Mines. * Figures as given in The Mineral Industry of the British Empire and Foreign Countries, Statistical Summary, published by The Imperial Institute, London. * Exports. * Approximate production. u Asbestos, vol. 15, no. 12. June 1934. p. 16. V Coot Australia............. Europe: AHucsletiruiam. Luxe gsSStes* Denmark* -- EFisntloannida.............. France......... Germany.-- Greece......... Hungary--Italy............ LNaettbveiarla..o--u> Norway,.-- Poland..-- Portugal Rumania-- Spain......... Sweden.-- Switzerlnnc V. s. S. RUnited Kin Yugoslavia Total, Ei Total by contii Asia.......... Ainca....... North Am South Am* Australia. Europe- Total, w : Estimate l Ashes in far n develop The tween 3 ASARCO ALV 0006263 asbestos . ii furnishes interesting data on a fr0 ^wmpiled by "Tropag" AsSest- und ,,r^re Germany, from data supplied by I- of the countries concerned. Lp>/0* Of asbestos, 19-11-33 (long tons) .*932 j 1933 Consumption 1931 1932 1933 93.311 5,000 Z6SQ \466 1.597 563 106.755 * 6,500 4 48.000 9.000 31386 14.354 * 7jo i 13,613 1 1,363 ! 7<l | 832 1 Poland... Norwav. Sweden...... ......... Estonia........ Finland!___ 968 IfWt............... ............ Lithuania____ Jugoslavia........ ........ Rumania........ ........ Australia....... ............ India.......... Africa............ *"' South America 'and' * 1.200 other countries- --------- - 342 *84 1.193 21 42 35j it 474 65 * 400 529 967 * 1.200 32 68 135 *50 303 *65 `750 1 uoo *750 Total, long tons.. Total, metric ronsVJI 253,893 257,955 205.179 208.462 255.095 259. 177 consumption for 1933. as given in this table aid total world production in that year, as i States Bureau of Mines (276.140 metric l by variations in stocks and materials in ipseredseonnts parodcoumctipoinlatpioluns oimf paoprptsaremnitnuws oersldjions in stocks, the figures are approximate kdiaa consumption as"shown in this table is use. with a steadily increasing market de li from stocks as well as from"current pronnpt^i ranges from 3,000 to 6.000 tons a ticaom^ totals, consumption balances rea- L isnmption. of asbestos, 1931 (In merr.r tons| affiSfesrassss S3*. JL 16. c,,. DOMESTIC DEPOSITS 19 World consumption of asbestos, 1931--Continued [In metric tone] Continent and country Produo lion Imports Exports Apparent consump tion ........ fouSern'Khodefn,^-- Union of South Africa... Total* Africa--.------ \**orrthynAmxletr.i.c.a.:. .............. United States........... ---- Total* North America.. couth America: * Brazil-------- Chile..--- Colombia-- Total. South America. , Australia. Europe: . Austria...------ Belgium Luxemburg. Bulgaria..--................ Czechoslovakia.......... Denmark........ ........... Estonia........ -............. Finland........................ France......................... Germany..................... Greece.......................... Hungary...................... Italy............................. Lama......................... Netherlands..... .......... Norway...................... Poland......................... Portugal...................... Rumania..................... ' Spain............... i.......... Sweden........................ Switzerland............. U. S. S. R. (Russia).. United HiDgdom____ Yugoslavia.................. Total, Europe......... Total by continents: Asia.............................. Africa........................... North America........... South America........... Australia..................... Europe......................... Total, world............ 39,234 15,960 | 45,1*4 j 141,502 4.615 146.117 109.165 109.165 39.085 15.315 44.900 1413.,551547 145,071 157 | 3 2.100 1.735 *406 *92.461 98.987 1.178 10.797 3 4.938 1.039 23 85 10.220 2a 154 76 627 S. 421 288 757 S10 345 i. 122 1 4.702 II 1.703 !. 713136 jt. 26.972 1 880 I.. 92.061 SS166 554 190 *505* 33.513 425 I 36.389 9.035 45.184 146.117 157 93.987 299.4S0 23.460 134 109,165 103 2.511 95.061 23a 434 7.508 44.900 145.071 234.168 37 97 139 145 --2. OSS 112.266 110.211 3287 38 103 1668 L 092 9.981 6 6.484 1,039 23 1.520 10.626 19.904 106 10. 6lt2g7 25 810 515 . 122 4.702 1.703 753 ' 55.704 56.547 850 '.57.659 24,637 413 uaau 103 2.563 157.659 295.716 * Estimate by Imperial Institute, London. DOMESTIC DEPOSITS chuysothe ALASKA Asbestos has been found near Shungnak and in the Jade Hills , in far northwestern Alaska, and several attempts have been made to develop the deposits. The Shungnak occurrences are close to the Kobuk River, be tween 150 and 200 miles from its mouth. According to Smith and ASARCO ALV 0006264 20 ASBESTOS Mertie.15 the asbestos occurs in small veins in close association with greenstone and serpentine. The veins, which are most abundant on the east side of Dahl Creek, consist mostly of short fiber, although some long fiber has been found. Samples of the latter were submitted to manufacturers some years ago. and they reported that the color was good but the fibers were too weak for high-grade uses. How ever, samples of strong, flexible chrysotile more than 6 inches long and apparently of very high grade'were obtained in 1932 from a deposit in this'locality. The asbestos appears to be of the slip-fiber type; therefore, it may be confined to shear zones. Stewartu states that three thin veins, the largest of which is about 3 inches wide, were uncovered at one point, and that some veins have been traced for at least a quarter of a mile. The deposit is undeveloped. Water transportation is available during the summer months. The Jade Hills lie north of the Kobuk River not far from its mouth. The asbestos deposits in these hills were worked in a small way for a short time many years a<ro, and in 1925 and 1926 in terest in them was revived and a trader at Kotzebue financed some new prospecting in the region. Xo definite information is available as to the kind or quality of asbestos found, but it probably is similar to that occurring at Sh'ungnak. ARIZONA Asbestos was first discovered in Arizona by Charley Xewton in 1872. He. with a small force of pioneers, fought a band of Indians, and during the engagement came upon an asbestos outcrop 3 miles northeast of Chrysotile on Ash Creek. Gila County, where tne largest asbestos mine in Arizona is now located. Xo "interest was taken in the deposit for many years. About 1900, chrysotile. asbestos was discovered in the Grand'Canyon and small quantities were mined on the north side opposite Grand View,.about 20 miles west of Grand View, and at other points. After these discoveries interest reverted to the Gila County occurrences, and in 1912 and 1913 many-claims were staked. Asbestos was found in numerous localities "over an area 60 miles lon<r and Go miles wide, most of which lies west of the San Carlos and Apache Indian Reservations. The asbestos occurs in the Apache formation, which, in the Salt River region, is represented chiefly by beds of quartzite and lime stone. It apparently originated "as an alteration product of the Mescal (Cambrian) dolomitic limestone due to metamorphism by diabase intrusions. It is associated with greenish and mottle'd serpentine. It occurs in cross-fiber veins, which are most abundant throughout the limestone close to the contact surfaces. Places where the limestone is much broken by the diabase intrusions are particu larly favorable for the formation of asbestos. The veins reach a maximum thickness of about 6 inches. The fibers may extend across the full width of the vein or they may be broken into two or more lengths. The veins are erratic and are not persistent for long dis tances. Intervals between them on the vertical face commonly vary 22 Smith, Philip S,, and Mettle, J. B.. Jr.. Geology and Mineral Resources of Northwest era Alaska: t\ S. Geol. Survey Bull. 815. 1930, pp. 344-345. 12 Stewart, B. D., Mining Investigations and Mine Inspection in Alaska: Biennium Ending Mar. 31, 1903, pp. 21, 20. i*JG d ASARCO ALV 0006265 ASBESTOS . nse association with ,,urs in small veins abundant on ^ m^^ortly o/sho" fiber, although |eeki^''^T^ o/tiie latter were submitted fhev reported that the color fe too?weak tor high-*rade uses. How- Wble chrvsotile more than 6 inches long iiah orade* were obtained in 1932 from a rife asbestos appears to be of the slip-fiber 'be confined to shear zones. Stewart15 5, the largest of which is about 3 inches ne point, "and that some veins have been c of a mile. The deposit is undeveloped, ulable during the summer months. i of the Koouk River not far from its its in these hills were worked in a small y }7ears ago, and in 1925 and 1926 inand a trader at Kotzebue financed some on. No definite information is available asbestos found, but it probably is similar ak. -ARIZONA -red in Arizona by Charley Newton in e of pioneers, fought a band of Indians, came upon an asbestos outcrop 3 miles ih Creek. Gila County, where the largest ; now located. No "interest was taken .s. About 1900. chrvsotile asbestos was nyon and small quantities were mined and View, about 20 miles west of Grand After these discoveries interest reverted :es, in 1912 and 1913 many claims fou^Bn numerous localities "over an liles^Wae. most of which lies west of idian Reservations. Apache formation, which, in the Salt chiefly by beds of quartzite and lime lted as iin alteration product of the b limestone due to metamorphism by ssociated with greenish and mottled -s-fiber veins, which are most abundant to the contact surfaces. Places where by the diabase intrusions are particuation of asbestos. The veins reach a ' inches. The fibers may extend across they may be broken into two or more c and are not persistent for long dism on the vertical face commonly vary Jr.. Oeototrr and Mineral Resources of Northwest. . 1930. pp. .`M4-345. Iona and Mine Inspection in Alaska: Biennium Bulletin 403 ASARCO ALV 0006266 DOMESTIC DEPOSITS 21 . 2 to 6 feet. Conditions are most favorable for mining where veral veins are close enough to each other to be worked from one funnel. Usually much barren rock must be mined to recover the fiber-bearing seams. The occurrences are quite different from the Canadian deposits, where fiber veins traverse massive serpentine irregularly. The nignesc-graae fiber, shown in figure 4, is soft and silky, has high tensile strength, and .is excellent for spinning purposes. A harsher, less desirable fiber, however, is associated with tne soft in many places. Arizona chrysotile is very low in irotf, therefore it is generally considered more suitable for electrical insulation than chrvsotile from other regions. According to Melhase,14 the asbestos deposits of Gila County may be grouped m five well-defined districts, as follows: 1. Mogollon Rim district at the northern boundary of the county. It contains some interesting occurrences that are too remote to en courage development. 2. Cherry Creek district, comprising about 75 square miles along the canyon of Cherry Creek. The southern end of the district is about 25 miles north of Globe. Considerable mining has been done, notably at the Riga, Triangle, and Aileen properties. 3. Sierra Ancha district, comprising albout 60 square miles ad joining the western boundary of the Cherry Creek district. The principal properties in this area are the Clark, Riga, and Ameri can ores. 4. Chrysotile district, including about 100 square miles on both sides of Salt River. Chrysotile, where the Johns-Manville mine, the largest asbestos mine in the State, is located, lies 24 miles northnortheast of Globe. Other important properties are the Regal, the Arizona Asbestos Co., and the Bear Canvon Asbestos Co. More than a dozen other properties have been developed to varying degrees. 5. Globe district, covering about 60 square miles, extending from Copper Hill, 4 miles north of Globe, eastward toward the Sail Carlos River. The Apache mine is the most important in this area. The location of the deposits, most of which are many miles from a railroad, and the long and costly rail haul to eastern markets have confined mining chiefly to the highest-grade crude fibers. Haulage charges from most of "the mines in the Chrysotile district, the most productive area in Arizona, to Globe range from $22 to $05 a ton. Very few of the properties have produced during recent years. Production began m 1913 and has never exceeded a few hundred tons a year, attaining a maximum of 11200 tons in 1920. A new highway, constructed in 1933, from Springerville to Globe lowers the cost of transportation and may encourage enlarged development. CALIFORNIA Asbestos occurrences in California are numerous but the history of their development has been disappointing. The first reference to chrysotile in the Mineral Resources chapters of the United States Geological Survey was in 1901. In that year a small production was 14 Melhase. Jobn. Asbestos Deposits la Arizona: Eng. and Min. Jour. Press, vol. 120, no. 21, Nov. 21. 1025, pp. 305-10. ASARCO ALV 0006267 22 ASBESTOS reported in Riverside County ana occurrence in Calaveras County was mentioned. A small output was reported from Placer County in 1905: but. although several new deposits were recorded between 1906 and 1911. none of them bore promise of a large supply. Slip fiber was found in Sierra County in 1912. Samples of chrysotile obtained in Shasta and Napa Counties in 1913 were not of promising quality. Up to 1914. asbestos had been reported in 12 counties! Production in Shasta, Placer, Calaveras, and Alameda Counties ag gregated 65 tons in 1914. In 1915, a manufacturer of asbestos pipe covering and shingles at Oakland reported purchase of 80 tons of fiber in" Placer, Alameda, and Contra Costa Counties. Three car loads of nonspinning fiber were shipped to Oakland from near Sims in Shasta County in 1916. The asbestos is said to occur in cross fiber veins, in serpentine, which would indicate that it is chrysotile, but shipments from this locality in 1922 were reported as amphibole. The most- productive deposit in California is 2% miles northwest of Washington, Nevada County, where the fiber occurs in a large area of serpentine. Mining was begun about 1917. A 300-foot, tunnel was driven into a serpentine hill on a 6-percent upgrade and a 150-foot raise was put through to the surface. The rock was mined by a glorv-hole method, dropped through the raise, and trammed' through the tunnel. A mill having a capacity of 100 tons a clay was equipped with stamps, screens, fioerizers, and air-suction pipes. Short fiber and a small quantity of spinning fiber were pro duced, but activity ceased with the sale in 1923 of a small tonnage of fiber milled in 1921. Much of the output was used in the manu facture of flooring in San Francisco. A deposit that bears promise of commercial importance was reported in the Chicago Park dis trict in 1937. Another property that attained some prominence is about 6 miles east of Copperopolis. Calaveras County, in a serpentine belt having a maximum width of 2.700 feet. Prospecting and developing con ducted in 1920 and 1921 revealed a commercially mineralized area about 1.400 feet long and 400 feet wide. In some places the ser- Eentine rock carries 12 to 15 percent asbestos in cross-fiber veins, ut the average of workable rock is much lower. A 5-percent re covery is recorded for one period of mill operation. The fiber is of paper-stock grade or shorter. A small crushing and fiberizing mill, capable of handling about 30 tons of ore a day,began operation in 1921. Underground workings consist of several* tunnels, the long est of which was driven. 278 feet into the hill Very little fiber was produced, and no activity has been reported since 1923. A deposit was developed about 1920 and a mill built in 1921 on a property 2% miles from Hernandez in southern San Ber.ito County. A small tonnage of fiber was produced from 1923 to 1926, and thereafter activity ceased. A large asbestos deposit was reported in Napa County, and plans were under way for a $20,000 mill in 931, but the project did not materialize. Small quantities of asbestos were produced 9 miles southwest of Monticello in 1932, and a mill was built in 1933. In 1931, asbestos occurring in irregular veins in dark-green, ser pentine was mined in an open-cut near Carrville, Trinity County. Several tons of chrysotile of good quality and averaging % inch in length were obtained. DOiffif In 192S. 7 or 8 tons of asbe: dletown. Lake County. \sbestos of good qual>* t northwest of Coalinga. : produced in 191S and 1919 wa 1 Small quantities were proc Countv. in 1917, and near Va'. Alame'da County in 1918. Asbestos deposits have bee 31.?; miles front Cisco, Place County; Edgewood, Siskiyou The maximum production in the State mineralogist in 19: duction in California, by year represent both chrysotile and 1900 was classed as amphibol A*bextti< product Year | Tons Value Yea: ; . .. 1592................. . i$w.................. i yOO................... 30 31.500 30 1. buc3U l.aw 4.2C0 cc 3.900 1.530 2. M0 50 2.250 1.CU0 lu 2UU 30 750 50 2.2/0 no 4.400 *903........ lyos... IKK!........ 1*05........ JW&........ 1910........ 1911........ :w2___ m2___ WU........ 1^16___ : Annual details concealed unoer "tmppor A deposit of asbestos near ( Idaho line, .was developed t. The chrysotile occurs with se: tion to that found in Arizona associated with diabase inti States Bureau of Alines in li brittle than fiber from Cana 1923 and additional machine! has been almost negligible. Chrysotile asbestos, appart. Malheur County. . The Montbestos Co. (forme tion) operated the mine in 1 mitted to buyers during that; "California Mineral Production anof California Div. of Mines Lull. 111.. '! ASARCO ALV 0006268 ASBESTOS nty ana occurrence in Calaveras County output tvas reported from Placer County deposits were recorded between m promise of a large supply. Slip County, in 1912. Samples of chrysotile >a Counties in 1913 were not of promising estos had been reported in 12 counties, er, Calaveras, and Alameda Counties ag in 1915, a manufacturer of asbestos pipe Jakland reported purchase of 80 tons of and Contra Costa Counties. Three carwere shipped to_ Oakland from near Sims The asbestos is said to occur in crosshich would indicate that it is chrysotile, ality in 1922 were reported as amphibole. osit in California is 2% miles northwest junty, where the fiber occurs in a large rg was begun about 1917. A 300-foot rpentine lull on a 6-percent upgrade and through to the surface. The rock was ethod, dropped through the raise, ancl ;L A mill having a capacity of 100 tons tamps, screens, fiberizers, and air-suction nail quantity of spinning fiber were prowith the sale in 1923 of a small tonnage uch of the output was used in the man'uFrancisco. A deposit that bears promise was reported in the Chicago Park dis- .tained some prominence is about 6 miles eras County, in a serpentine belt having feet Prospecting and developing conjvealgAa commercially mineralized area 400|^B: wide. In some places the ser15 pffcent asbestos in cross-fiber veins, le rock is much lower. A 5-percent re period of mill operation. The fiber is lorter. A small crushing and fiberizing >out 30 tons of ore a day,began operation kings consist of several" tunnels, the long278 feet into the hill. Very little fiber ity has been reported since 1923. about 1920 and a mill built in 1921 on m Hernandez in southern San Ber.ito of fiber was produced from 1923 to 1926, ed. was repotted in !Vapa County, and plans 000 mill in 931, but the project did not ies of asbestos were produced 9 miles .932. and a mill was built in 1933, ng in irregular veins in dark-green serpen-cut near Carrville, Trinity County, f good qualify and averaging % inch in DOMESTIC DEPOSITS 23 In 1928, 7 or 8 tons of asbestos were obtained 10 miles from Middletown, Lake County. Asbestos of good quality was reported from a deposit 27 miles northwest of Coalinga, Fresno County, in 1918. A small tonnage produced in 1918 ana 1919 was sold in 1925. 1 Small quantities were produced 2y2 miles east of lone, Amador County, in 1917, and near Valley Springs, Calaveras County, and in Uameda County in 1918. Asbestos deposits have been reported at Towle, Iowa Hill, and gy,, miles from Cisco, Placer County; at Goodyears Bar, Sierra County; Edgewood, Siskiyou County; and Tolon,"Monterey County. The maximum production in any one year was 410 tons reported by the State mineralogist in 1921. The following table15 shows pro duction in California, by years, since 1887. The figures in thistsble represent both chrysotile and amphibole. The entire output prior to 1900 was classed as amphibole. Asbestos production in California, 1887-1915 Year Tons Value Year Tons Value Year Tons Value Mg*.................... ............. 1 30 51,800 30 1.S00 71 4,260 66 3.960 30 1.S30 50 2.500 50 2,250 25 1000 10 200 30 750 50 1.250 HO 4.400 i 1903.................... 1901.................... 1906.................... 1907.................... 1908.................... 1909.................... 1910.................... 1911.................... 1912.................... 1913.................... 1914.................... 1915.................... 1916.................... 1917.................. 1918.................... i Annual details concealed under "unapportionod." 10 5162 70 3,500 70 3,500 70 6.100 65 6.500 700 20,000 125 500 90 2.700 47 1.175 51 1,530 143 2.560 145 2.3S0 136 10. 225 9.903 MONTANA 10101 ... 1920 `..................; SC.310 1922.................... 50 1923.................... 1924..................... 1925*.................. 1926`.................. 20 70 25 1927*.................. 1928*.................. 13 1929*.................. 1930*.................. 219 1931.................... 19321.... ......... ... 1934*..............J 1935.... ..............'.i.............. 4.750 1,650 I. ICO 3,2.4 A deposit of asbestos near Cliff Lake, Madison County, close to the Idaho line, was developed to some extent between 1917 and 1923. The chrysotile occurs with serpentine in limestone, a similar associa tion to that found in Arizona. The asbestos-bearing zone is closely associated with diabase intrusions. Samples sent to the United States Bureau of Mines in 1929 were found to be weaker and more brittle than fiber from Canada or Arizona. A mill was begun in 1923 and additional machinery was delivered in 1926, but production has been almost negligible. OREGON Chrysotile asbestos, apparently of good quality, is reported from Malheur County. The Montbestos Co. (formerly United Asbestos Products Corpora tion) operated the mine in 1934 but made no sales. Samples sub mitted to buyers during that year were said to be satisfactory. " California Mineral Production and Directory of Mineral Producers for 1931: Mate of California Div. of Mines Bull. 111. August 1935. p. 78. ASARCO ALV 0006269 24 ASBESTOS VEBMOXT Although asbestos was discovered in Vermont in 1S24. no interest was taken in it until M. E. Tucker found a chrysotile vein while fell ing trees on the eastern side of Belvidere Mountain in 1892 or 1893. Its resemblance to the Canadian fiber was recognized immediately, and it was later found to occur over a considerable area in Lamoille and Orleans Counties. The Vermont fiber is chrvsotile similar in character and occurrence to that found at Thetford Mines. Quebec, the deposit being regarded as a southward extension of the well-known Canadian belt. The asbestos is of two kinds--cross-fiber veins passing irregularly through serpentine and slip fiber lying parallel to sliekensided surfaces. Most of the cross-fiber veins are narrow, those over three-fourths inch in width being uncommon. Keith and Bain,16 after a detailed study of i he veins, decided that the asbestos had been introduced as a- vein filling material in torsion cracks and crush fractures. Matched struc tures on opposite walls of the veins are common. They found little evidence in support of a replacement theory. The slip fiber ranges from a fraction of an inch to 3 or 4 inches long ana is somewhat coarser than the cross fiber; however, it is not suitable for spinning. The claim has been made that the proportion of fiber to rock runs 8 to 12 .percent, which is somewhat greater than in the Canadian field. The yield of spinning fiber, however, is very small. Asbestos-bearing rocks occur in four prominent localities in La moille and Orleans Counties. The first occurrence, which is unde veloped. is about 2 miles northeast of Lowell. It. consists of numerous cross-fiber veins and some slip fiber in serpentine. The second de posit, northwest of Lowell in the vicinity of `Westfield, is in the form of a belt several miles long and a mile wide. Considerable slip fiber and cross fiber occur in places, but none has been mined. In the third locality, which is southwest of Lowell near Mount Belvidere. slip fiber predominates. A mill was erected in this district in 1902 by the Kew England Asbestos Mining Milling Co., but was operated only 6 months. The fourth serpentine area, extending about 2 miles eastward from the third, occupies a prominent bluff on the shoulder of Belvidere Mountain. Both slip-fiber and cross-fiber veins occur, the latter providing a small amount of crude asbestos. On this prop erty, in 1907. the Cowell Lumber & Asbestos Co. erected a mill with a daily capacity of about 200 tons of rock. Production was first recorded in 1908, and in 1909 the industry was so active that Ver mont became the chief asbestos-producing State. In 1910, the output increased 24 percent over that in 1909. In 1911 the total production of the United States, 7,604 tons, was largely from Vermont. During that year considerable no. 2 crude was obtained. In 1912. Vermont, with a production of 4.403 tons, had the distinction of being the only asbestos-producing State in the Union, but for several years there after no activity was noted. The industry*was revived in 1920 by the Asbestos Corporation of America but not in the location formerly most productive. Since then operations have been confined to the opposite side of the deposit "Keith. Stanton B.. and Bain. George W,, Chrj-sotUe Aebestos. I, Chrytotile Veins: Boon. Geo]., vol. 27. no. 2. 1032. pp. 16S-18S. a"ftiltlhinegfoCrom. erSqf: or m. spuming t dfiuiy extensive but. there was i company was i Asbestos Corpo the plant in ope more than doub kets led to some has increased s' acquired by Ve Vermont Asbes ami with plant anticipated. Ij asbestos. The One important employeil. alson.', A small pro in Ict'd ana f> area of approx S miles south square miles 2i The mineral o are more than appears in pluc a small mill i ore a day. A little fiber hat tos Shingle C Casper Mount! Occurrences City. Fremont have hoc been < land. Platte G other places, t relatively low- Although m Carolina, chry 2 inches wide in 1902. An has been repot of Spruce Pirn Jackson Count County; and n ASARCO ALV 0006270 3EST0S RMONT red ' Vermont in 1S24, no interest :r ft__. a chrysotile vein while fellBelviclere Mountain in 1692 or 1893. i fiber was recognized immediately, iver a considerable area in Lamoille similar in character and occurrence Quebec, the deposit being regarded e well-known Canadian beltT The er veins passing irregularly through rallel to slickensided surfaces. Most w. those over three-fourths inch in nd Bain,TM after a detailed study of cos had- been introduced as a veinmd crush fractures. Matched strucins are common. They found little nent theory. The slip fiber ranges or finches long and is somewhat ;ver, it is not suitable for spinning. i proportion of fiber to rock runs 8 greater than in the Canadian field, ver. is very small. n four prominent localities in La ke first occurrence, which is undeof Low-11. It consists of numerous her in serpentine. The second devicinity of "Westfield, is in the form mile wide. Considerable slip fiber none has been mined. In the third -owell near Mount Belvidere. slip erect*-5 in this district in 1902 by g St ling Co., but was operated ntine area, extending about 2 miles a prominent bluff on the shoulder p-fiber and cross-fiber veins occur, it of crude asbestos. On this prop& Asbestos Co. erected a mill with ns of rook. Production was first industry was so active that Verducing >tate. In 1910, the output 909. In 1911 the total production is largely from Vermont. During was obtained. In 1912. Vermont, d the distinction of being the only 'nion. but for several years there- 20 by the Asbestos Corporation of formerly most productive. -Since ro the opposite side of the deposit _ Chrysolite Asbestos. X. Chrysotile Velas: DOMESTIC DEPOSITS 25 jt the former cpiarry site of the New Eneland Asbestos Mining & filling Co. Sim fiber predominates in this region, there being little no spinning fiber. The reserves of asbestos-bearing rock are evi dently extensive. A mill was built and experimental runs were made {jiic there was no commercial production until 1929. In 1928, the t.0iupany was reorganized under new ownership as the Vermont ^Vebestos Corporation of America. The new company quickly put the plant in operation, producing 1,049 tons of mill fiber in 1929. and more than doubled that quantity in 1930. Although depressed mar kets led to some reduction in output thereafter, since 1932 production has increased ^substantially. In February 1936 the properties were acquired by Vermont Production Co., Inc., subsequently named the Vermont Asbestos Corporation, a subsidiary of The Euberoid Co., and with plant additions and improvements an increase in output is anticipated. In 1934, the former operators produced 6 grades of asbestos. The longest grade was shingle stock testing 0-2-10-4. One important use Ts for manufacture of'niolded brake linings. It is employed, also, in asbestos-cement shingles, asbestos paper, pipe cov ering." paint. and boiler covering. The present owners use part of the output in their own products and sell the remainder to other asbestos-product manufacturers. WYOMING A small production of chrysotile was reported from Wyoming jn 1892 ana from 1906 to 1912. Asbestos occurs in a serpentine area of approximately 4y2 square miles on Casper Mountain about S miles south of Casper and. in the Smith Creek area of about 7 square miles 20 miles southeast of Casper, both in Natrona County. The mineral occurs principally as cross-fiber veins, few of which are more than an inch across, but a minor quantity of slip fiber appears in places. In 1910, the Wyoming Consolidated Co. operated a small mill in the Smith Creek area, "handling about 30 tons of ore a day. A mill was built on Casper Mountain in 1911. Very little fiber has been produced in either locality, but the Patee Asbes tos Shingle Co. reported production of 200"tons in 1934 from its Casper Mountain property. Occurrences of spinning-grade asbestos near Lander and Atlantic City, Fremont County, were reported in 1919, but the properties have not been developed. A small quantitv was obtained at Wheatland. Platte County, in 1920. Chrysotile has been found in several other places, but most of the occurrences throughout the State are relatively low-grade, short fibers. OTHER OCCURRENCES Although amphibole is the prevailing type of asbestos in North Carolina.'chrysotile also occurs in several places. Chrysotile veins 2 inches wide were found near North Wilkesboro, Wilkes County, in 1902. An open-cut 100 feet long was made, but no production has been reported. Other occurrences have been noted 8 miles westof Spruce Pine, in Yancey County: near Glenville and Sapphire, in Jackson County: on the western Hopes of Rich Mountain, Watauga County; and near Elk Creek, Ashe County. 'I \ ASARCO ALV 0006271 2G ASBESTOS A deposit near Round Hill. Loudoun County, Ya.. was reported in 1894. Small stringers of asbestos also occur in massive serpentine near Great Falls. Fairfax County. Chrysotile was found in 1902 near Ishpeming. Marquette County, Mich..'and some development work was done. AHPHIBOIE ALASKA Asbestos said to be of the ampliibole variety occurs on Admiralty Island and at Chitina on the Copper River.'_ A little development work has been done, but the low price of amphibole fiber discourages development so far from markets. CALIFORNIA As early as 18S2 asbestos deposits were worked in San Bernardino. San Diego. Calaveras, and Placer Counties, and in 1883 and 1884 occurrences in Butte. Fresno. Los Angeles. Tulare. Mariposa, and Inyo Counties were noted and some of"them were developed. Pro duction in 1882 was 1.200 tons: in 1883. 1.000 tons: and in 1884.1.000 tons. In 1885. a small mine was opened at Windsor in Sonoma Countv. and fiber of good quality was reported from Del Norte and Yolo Counties. Sales of asbestos in the United States of 30 tons in 1889. 71 tons in 1890. and 66 tons in 1891 were credited entirely to California. In 1892 most of the production was from Wyoming, with small quantities from Oregon and California, but again in' 1893 California, with an output of 50 tons, was the only producing State. The mines were iale in 1894 but produced 90. tons in 1895. A small and gradually decreasing output was noted from 1897 to 1900. All the production up to the latter year was classed as amphibole asbestos. Evidently it was used chiefly in San Francisco and Oakland for making pipe and boiler coverings, packings, and roofing. A slip-fiber anthophyllite was mined for several years near Sims, Shasta County, but no activity has been noted since 1923. A deposit of amphibole asbestos associated with serpentine near Chandlers. Kern County, was developed in 1928. Several short tunnels and open-cuts were made, but evidently the operation has not passed the development stage. Production during recent years has been almost negligible, and there is no prospect at present of the industry attaining importance. GEORGIA Occurrences of amphibole asbestos in Georgia are of two kinds: (1) Mass fiber, consisting of aggregations of short fibers representing a complete alteration of the original igneous rock; and (2) longfibered asbestos, occurring in veins associated with partly altered peridotite, talc, chlorite, and serpentine. Georgia has been the most consistent producer of amphibole asbes tos of any of the States. The largest quantity has been obtained from deposits on or near Sail Mountain in th'e vicinity of Helen. Santee, Cleveland, and Nacoochee, White County. These deposits DOX ve produced with some : -mail way during earlier ilnSrliophvlhte type. It is c Carried'is fiber. Thebe feathering has made it sof oCk is less desirable and i 0f the- best fiber, therefore, available high-grade materi for use in a mill at Gaines is employed principally' paint manufacture. 1 Another production cente: 1924 to 1927, is Hollywood, which occurs in a deposit r silky than that at Sail Moui hammer-mill methods of fi grades of asbestos were pr heat insulation and as^filler f boxes, and rubber. Little oi 1927. A large deposit of : county about 11 miles northby road from Nacoochee. Wh 'From 1923 to 1927 a smal, from a property on Bear C Barrow County! It was use Asbestos was mined abotv Rabun County. The mineral from alteration aloiicr fractu: trusion. Many other occurre Fiber 6 to 7 inches long c about 2 miles southeast of Me Long slip fiber occurs in wether County. Manv other undeveloped u ' tt Cl_;___,, The only asbestos deposit i: mercially is in Idaho County The deposit consists of brittle lenticular masses, some of wbi It is regarded as an alterati Asbestos Manufacturing Co. p of years prior to 1918. In S< chased by the Western Miner; was reported by this company, iston, Idaho, acquired the prop ments in 1925. No sales have b ing to a press report in 1930. Wash., purchased the plant. T; ated in 1925; had a capacity of 0006272 ASARCO AL-V asbestos Hill Loudoun County, Ya., was reported of asbestos also occur m massive serpentine Co*" * v i9v ear Ishneming, Marquette County, ;ent work was done. amphibole ALASKA ie amphibole variety occurs on Admiralty the Copper River. A little development e low price of amphibole fiber discourages larkets. CALIFORNIA deposits were worked in San Bernardino, 1 Placer Counties, and in 1883 and 1884 mo, Los Angeles. Tulare. Mariposa, and and some of"them were developed. Pro ms; in 1883,1,000 tons: and in. 1884. 1,000 ine was opened at Windsor in Sonoma i quality was reported from Dei Norte - of asbestos in the United States of 30 490. and 66 tons in 1891 were credited : 1892 most of the production was from '.tines from Oregon and California, but vith an output of 50 tons, was the only nes were idle in 1894 but produced 90 i gradually decreasing output was noted i production up to the latter year was cos. Evidently it was used c'hieflv in l for making p'ipe and boiler coverings, wa. ned-for several years near Sims, vity has been noted since 1923. asbestos associated with serpentine near vus developed in 1928. Several short made, but evidently the operation has stage. Production during recent years .nd there is no prospect at present o'f the :ce. GEORGIA asbestos in Georgia are of two kinds: aggregations of short fibers representing i original igneous rock: and (2) long:n veins associated with partly altered serpentine. consistent producer of amphibole asbesThe largest quantity has been obtained all Mountain in the vicinity of Helen, jochee, White County. These deposits DOMESTIC DEPOSITS 27 have produced with some interruptions since 1894 and possibly in a small way during earlier years. The asbestos is of the mass-fiber anthophyllite type. It is claimed that 90 to 95 percent of the rock quarried is fiber. The best asbestos is near the surface, where weathering has made it soft and flexible. The solid, unweathered rock is less desirable .and requires different treatment. Resources of the best fiber, therefore, are relatively limited, and most of the available high-grade material is exhausted. The fiber is prepared for use in a mill at Gainesville about 27 miles from the deposits. It is employed principally for fireproofing, for insulation, and in paint manufacture. Another production center of some importance, particularly from 1924 to 1927, is Hollywood, Habersham County. The mass fiber, which occurs in a deposit about 90 feet wide, "is harsher and less silky than that at Sail Mountain. After much experimental work, hammer-mill methods of fiberizing were introduced and several grades of asbestos were prepared The products were sold for heat insulation and as^filler for composition flooring, plaster, batteryboxes, and rubber. Little or no production has been recorded since 1927. A large deposit of mass-fiber anthophyllite occurs in this county about 11 miles northwest of Clarkesville. It is 8 to 9 miles by road from Nacoochee, White County, the nearest railway station. "From 1923 to 1927 a small output o'f anthophyllite was reported from a property on Bear Creek 1y? miles northeast of Scatham. Barrow CountyI It was used principally for filtering acids. Asbestos was mined about 1880. 2 miles northwest of Burton. Rabun County. The mineral is long-fibered and woody. It resulted from alteration along fracture zones of an extensive peridotite in trusion. Many other occurrences are known in the county. Fiber 6 to f inches long occurs in an lS-inch vein in soapstone about 2 miles southeast of Moreland. Coweta County. Long slip fiber occurs in talcose rock north of Luthersville, Meri wether County. Many other" undeveloped deposits in the State have been described by Hopkins." IDAHO The only asbestos deposit in Idaho that has been developed com mercially- is in Idaho County about 14 miles southeast of Karniah. The deposit consists of brittle mass-fiber anthophyllite occurring in lenticular masses, some of which are 200 feet long and 35 feet thick. It is regarded as an alteration product of dunite. The Ivamiah Asbestos Manufacturing Co. produced in a small way for a number of years prior to 1918." In September 1921 the property was pur chased by the Western Mineral Co. of Kamiali, but no production was reported by this company. The Panhandle Asbestos Co. of Lew iston, Idaho, acquired the property in 1923 and reported small ship ments in 1925. No sales have been recorded since that year. Accord ing to a press report in 1930. the Diatom Products Co. of Seattle, Wash., purchased the plant. The mill, that was apparently last oper ated in 1925; had a capacity of 240 tons of ore a day and was equipped lT Hopkins. Oliver B.. Asbestos. Talc, and Soapstone Deposits of Georgia: Oeol. Survey of Georgia Bull. -HJ, H)H, pp. ASARCO ALV 0006273 28 ASBESTOS with crusher, rolls, screens, and air separators. The fiber was used for pipe and boiler covering, in wall plaster and paint, and as a binder in cements and asphalts. In 1922- equipment was installed for sawing fire blocks and insulating brick, but the project did not materialize. 1IARYLAXD Asbestos occurrences were noted in western Man-land as early as 1883. but no production worthy of mention was recorded until 1917. In that year a slip-fiber anthophyllite deposit was developed near Pylesville. Harford County. The asbestos occurs in gneissoid schists that have been softened by weathering. The veins generally are small, and the usable fiber is'confined to a zone near the surface.' The good asbestos extends to greatest depths along shear zones where movement and pressure have been greatest. Mining has been con ducted to a depth of about 50 feet. The fiber is unusually strong and tough, and is especially adapted to making acid filters: therefore, it is more valuable than anthopnvllite from other localities. It is prepared for market by the Powhatan Mining Co. at Woodlawn. a suburb of Baltimore. Before this deposit was discovered, supplies of acid-filter fiber were obtained from Italy. A little long-fiber anthophyllite. said to be similar to that mined at Pylesville, is found associated with talc in the Harford Talc & Quartz Co. quarry near Dublin, Harford County. JtOXTAKA A deposit of anthophyllite asbestos, said to be extensive, in Gallatin County, about 17 miles' south of Gallatin Gateway, is worked for a small production of insulating material. The fiber occurs in a dense, hard form but breaks down readily to a soft, fluffy mass. Occasional pockets and lenses contain strong, silky fiber, much of which is an inch or more in length. It is of spinning quality and is the only amphibole of such grade in the United States known to the Bureau. Peter F. Karst operated the property for several years, but in 1936 it was acquired by_ The Karstolite Co. This firm mines the asbestos and manufactures it into a wall and ceiling insulation sold under the trade name "Karstolite." A small shipment of anthophyllite was recorded in 1928 from a property on Rainey Creek. 7 miles northeast of Libby, Lincoln County." KORTH CAROLINA About 1928 a mill that would handle 35 tons of ore a day was built at Minneapolis, Avery County, for treatment of mass-fiber anthophyl lite occurring in that region. The mill equipment was improved considerably m 1935. and steps were taken to develop a market for prepared asbestos to be used in home insulation and in many other ways. A deposit near Plumtree, in this county, was developed some years ago, but very little fiber has been produced. A mill was built near Otto, Macon County, in 1928 but has not produced. A small output was reported in .1919 from a deposit of mass-fiber anthophyllite at Cane River. Yancey County. Deposits of anthophyllite occur also near Warlick, Burke County; on the >Tantahala River, Mao near Todd, Ashe Coe Caldwell County. Sistv-four tons of sold in 1892. In 1917 of Mount Vernon, Gra Baker County, was de: Development' work on a 310-foot tunnel was purposes was reported Amphibole asbestos; cross-fiber veins traver Gillespie Counties. TS of a considerable supp usual in amphibole-asl plied by Sellards and 1 Anthophyllite asbesi Bedford County. The and olivine. Tjnlike t: the best asbestos is th< occupying shear zones, inches' thick supplied c for treating the* asbesto able supply is probabh 1911. A small quantit; a preparation used by c A deposit of slip-fi' Franklin County. A s tons were obtained fron also near Boyce, Clarke County. The Asbestos-Talc P lington, Skagit County, talc, serpentine, and a used in boiler coverings, also manufactures "Asl rial, and "Asbestocite",; roofing paints and plast Asbestos has been mil in paints. Deposits haCounty, near Hamiltoi County; and S miles no Sellards. E. H.. end Baker 1935, p. 252. 134342*--37--------3 l asarco alv 0006274- ASBESTOS and air separators. The fiber was used ig', : vail plaster and paint, and as a ilts. . 1922 equipment was installed for ulating brick, but the project did not MARYLAND ji ! noted in western Maryland as early as thy of mention was recorded until 1917. ithophyllite deposit was developed near The asbestos occurs in gneissoid schists .* weathering. The veins generally are confined to a zone near the surface. The reatest depths along shear zones where e been greatest. Mining has been conj feet. mg and tough, and is especially adapted fore, it is more valuable than anthopnylis prepared for market by the Powhatan -uburb of Baltimore. Before this deposit cid-filter fiber were obtained from Italy, vllite, said to be similar to that mined at l with talc in the Harford Talc & Quartz ford County. J j j | MONTANA j i asbestos, said to be extensive, in Gallatin ! l of Gallatin Gateway, is worked for a .g material. The fiber occurs in a dense, : eadilv to a soft, fluffy mass. Occasional trong, silky fiber, much of which is an | of s: `-ming quality and is the only am- ; .e C d States known to the Bureau.j property for several years, but in 1936 ! tolite Co. This firm mines the asbestos all and ceiling insulation sold under the mpliyHite was recorded in 192S from a 7 miles northeast of Libby, Lincoln i RTH CAROLINA Id handle 35 tons of ore a day was built v. for treatment of mass-fiber anthophyli. The mill equipment was improved ns were taken to develop a market for in home insulation and in many other ' ree, in this county, was developed some - has been produced. . Macon County, in 1923 but has not as reported in 1919 from a deposit of Cane River. Yancey County. Deposits near Warlick, Burke County; on the | j . | j ; ! ; : DOMESTIC DEPOSITS 29 Yantahala River, Macon County; near Bakersviile, Mitchell County; near Todd. Ashe County; Brevard, Transylvania County: and in Caldwell County. OREGON Sixty-four tons of amphibole asbestos produced in Oregon were sold in 1892. In 1917 a small mine was operated a few miles north of Mount Vernon, Grant County. Asbestos occurring near Hereford, Baker County, was described in 1922 as a soft, long-fibered tremolite. Development work on the property was reported in 1925. and in 1926 a 310-foot tunnel was driven. A small production, for experimental purposes was reported in 1929. TEXAS Amphibole asbestos approaching tremolite in composition occurs in cross-fiber veins traversing serpentine in four localities in Llano and Gillespie Counties. The veins are very irregular, but there is promise of a considerable supply. The occurrence of cross-fiber veins is un usual in amphibole-asbestos deposits. Further information is sup plied by Sellards and Baker.18 VIRGINIA Anthophyllite asbestos occurs about. 12 miles south of Bedford. Bedford County. The prevailing associated minerals are hornblende and olivine. Unlike the mass-fiber deposits of Georgia and Idaho, the best asbestos is the slip-fiber type, occurring in veinlike masses occupying shear zones. Several veins have been noted, and one IS inches* tluck supplied considerable fiber from 1904 to 1911. A mill for treating the asbestos was erected in Bedford in 1903. The avail able supply is probably small, as very little has been produced since 1911. A small quantity has been used in the manufacture of Tenax. a preparation used by dentists. A deposit of slip-fiber amphibole occurs also at Rockymount. Franklin County. A shaft was sunk to a depth of 40 feet, and 40 tons were obtained from this mine in 1907. Deposits have been noted also near Boyce, Clarke County, and 8 miles from Roanoke. Roanoke County. WASHINGTON The Asbestos-Talc Products Co. developed a property near Bur lington, Skagit County, and has produced a small tonna'ge of mixed talc, serpentine, and asbestos since 1930. The milled product is used in boiler coverings, roofing, and acoustic plaster. The company also manufactures "Asbesto-Ftll", a heat-insulating building mate rial, and `'Asbestocite", a compound of asbestos fiber and talc used in roofing paints and plastics. Asbestos has been mined near Pateros. Okanogan County, for use in paints. Deposits have been reported near Leavenworth, Chelan County, near Hamilton. Lyman, and at other points in Skagit County ; and 8 miles north of Chewelah, Stevens County. w$ollarfs. E. II., and Baker. Charles Laurence: Economic Geology of Texas, part 3, 1933. p. 252. 134342*--3T------ 3 ASARCO ALV 0006275 f 30 ASBESTOS OTHEE OCCURRENCES Many other occurrences of nmphibole asbestos were known from 1SS0 to 1905. The following localities, mentioned in early records, evidently hacl small importance as sources of supply: Staten Island and Long Island. X. Y.: New Brunswick. X. J.: Media and Colerain, Pa.: Lawrence County. $. Dak.: Stevens Point. Wood County. Vis.: Six Mile and Pickens. S. C.: Baraga County. Mich.: and New Hart ford, Conn., where a small mill was operated in 1903. From 1901 to 1906 a small output of asbestos was reported near Dalton. Mass. It was first thought to l>e chrysotile but was identified definitely as anthoph.vllite in 1906. Blue asbestos (crociclolite) occurs at Beacon Pole Hill near Manville, Providence County, B. I., but not in com mercial quantities. FOREIGN DEPOSITS Buroui r-t Min*** CANADA The asbestos deposits in the eastern townships of the Province of ' Quebec, Canada, have been famous since 1878. They are situated 100 to 175 miles from Montreal and somewhat nearer Quebec, occupying a stretch of high ground known as the Xotre Dame Hills--an ex tension into Canada of the Green Mountains of Vermont. The hills continue northeastward to the Gaspe Peninsula, and serpentine is exposed in many places throughout their length. An asbestos de posit was developed at Port Daniel on the Gaspe Peninsula in 1919. Commercial asbestos occurs in two places--the Thetford Mines dis 4 trict, described later, and the Eden (Vt.). district, which has been i covered in the discussion of domestic deposits. The Quebec area, about 70 miles long and a maximum of 5 or 6 miles wide, lies between Danville and East Broughton. Within this section are six producing centers--East Broughton, Robertson. Thet ford Mines, Black Lake, Coleraine, and Danville. The geology of the district has been covered in detail by Cirkel.15 The asbestos, a chrysotile of exceptionally high quality, occurs in a very extensive serpentine formation of Cambrian age appearing in place's as moun tain masses rising 700 to 1,000 feet above the surrounding country. It is said to be the largest area of serpentine near the eastern coast of Xortli America. The serpentine is regarded as an alteration product of the ultrabasic rock dunite, which consists essentially of olivine and chromite. In the process of alteration, serpentinization takes place first along irregular cracks in the olivine, and the wavy contortions of the filaments led to application _ of the name "ser pentine." As alteration of olivine to serpentine involves an increase in volume of more than 30 percent, progressive disruption and frac turing would occur. Cirkel20 attributed the origin of the chrysotile to columnar crystallization of serpentine in cracks and fissures' The process is somewhat obscure, but he presumed that the serpentine, which thus takes the form of bundles of extraordinarilv fine filaments, crystallized from aqueous solutions acting upon the vein walls. Cirkel, Fritz. Chrysotile Asbestos--Its Occurrence, Exploitation, Milling, and Uses: Mines Branch, Canada Dept, of Meins, 2d ed. 1910, Cirkel, Fritz, Work cited, pp. 92-95, asarco alv 0006276 ASBESTOS OTHEB OCCtnUtEJTCES es c 'nphibole asbestos were known from win^ realities, mentioned in early records, o'rtance as sources of supply: Staten Island Xew Brunswick. X. J.: Media and Colerain, >. Dak.: Stevens Point. Wood County, Wis.; C-: Baraga County, Mich.; and Xew Hart.11 mill was operated in 1903. From 1901 to sbestos was reported near Dalton. Hass. It chrvsotile but was identified definitely as 31ue asbestos (crocidolite) occurs at Beacon Providence County. E. L, but not in com- "OEEIGX DEPOSITS CACTADA n the eastern townships of the Province of n famous since 1ST8. They are situated 100 -al and somewhat nearer Quebec, occupying l known as the Xotre Dame Hills--an exie. Green Mountains of Vermont. The hills :o the Gaspe Peninsula, and serpentine is throughout their length. An asbestos deort Daniel on the Gaspe Peninsula in 1919. irs in two places--the Thetford Hines disl the Eden (Vt.). district, which has been of domestic deposits. t 70 miles long and a maximum of 5 or 6 Janville and East Broughton. Within this centers^--East Broughton, Eobertson, Thet- Coleraine. and Danville. The geology of ^red detail by Cirkel.13 The asbestos, a iv hie quality, occurs in a very extensive Cumbrian age appearing in places as rnoun- 1,000 feet above the surrounding country, -t area of serpentine near the eastern coast * serpentine is regarded as an alteration rock dnnite, which consists essentially of t the process of alteration, serpentinization egular cracks in the olivine, and the wavy mts led to application of the name "ser if olivine to serpentine involves an increase 0 percent, progressive disruption and fractel:o attributed the origin of the chrvsotile n of serpentine in crack's and fissures.' The ure. but he presumed that the serpentine, of bundles of extraordinarily fine filament?! s solutions acting upon the vein walls. `stns--Its Ordinance. Exploitation, Milling, and .jins. 2d edM 1010. *2-05* ASARCO ALV 0006277 FOREIGN' DEPOSITS 31 Cirkel11 outlines the successive steps of formation of the asbestos as follows: 1. Intrusion of olivine (dunite) through the earth crust from below. 2. Gradual alteration of the rock to serpentine through hydration, and per haps loss of silica, increase in volume. 3. Slow readjustment of the rock masses, resulting In the formation of joints and slickensides. 4. Subsequent formation of fissures as receptacles for asbestos fiber, through shrinkage of the rock and also through injection of granite dikes. 5. Infiltratiou of serpentinous solution from the sides of the wall through process of segregation, and subsequent slow crystallization of chrysotile. Cookehas made the most comprehensive study of the origin of chrysotile asbestos veins in Quebec. Three hypotheses as toormin have been advanced: (1) Replacement of massive serpentine by asbescos, (2) fissure-filling by circulating solutions, and (3) solutions or vapors penetrating through pores of the wall rock and depositing asbestos in tight fissures, the growth of the fibers pushing the walls apart. Although some objection may be raised to tne last-mentioned theory, Cooke concludes that it furnishes the most adequate explana tion of the conditions existing throughout the region. .The most seri ous objection to the theory of fissure-filling by circulating solutions is the numerous occurrence of closed veins showing no connection with channels through which solutions could flow. In some places the fiber is very soft and flexible, while in others it is somewhat harsh and brittle. To determine a reason for this harsh ness, Cooke53 made very careful analyses of purified fibers of both varieties. He concluded from the results that the harshness is due primarily to the presence of talc. Keep -* reached a similar conclu sion regarding Rhodesian chrysotile. Almost the'entire output of the Black Lake, Thetford, and Dan ville areas is derived from cross-fiber veins ranging in width from hair lines to 4 or 5 inches and, rarely, even wider. 'The bulk of the production is obtained from veins 14 to Ys inch across. Width of veins is important because it governs largely the length of fiber. Fortunately the fiber as a rule breaks easily from the wall rock. Figure 5 shows a typical occurrence of asbestos veins in the Quebec district. Slip fiber originating along slickensided fault planes as a result of slow readjustment of the rock masses at a later time forms the chief product of the East Broughton area. The fibers are matted together more or less in parallel position, and therefore appear to be longer than they really are. Slip fiber, as- a rule, is less valuable than cross fiber. The percentage of fiber in the rock is low. According to Ross.-'3 G.203.970 tons of rock were mined in 1929 and total fiber recovery (excluding asbestic) was 311.204 tons. The yield was 5 percent o'f the total rock mined and 7.7 percent of the rock milled. The value Cirkel. Fritz. Work cited, p. 101. -Cooke. H. C.. Asbestos Deposits of Thetford District. Quebec: Econ. Geol.. rol. 01. no. 4. Juno-July 11106. pp. 055-076. 54 Cooke. H. C.. The Composition of Asbestos and Other Fibres of Thetford District. Quebec: Trans. Roy. Soc. Canada. 2d ser.. vol. 29. .sec. 4. May 1935. pp. 7-19. 24 Keep. F. E.. Oeolozy of the Shabani Mineral Belt. Bellngwe District: Oeol. Surrev, So. Rhodesia. Bull. 12. 1929. J. Chrysotile Asbestos in Canada: Mines Branch, Canada Dept/MIiw Bull. 707. 1931, table 1. p. 60. ASARCO ALV 0006278 asbestos 32 of the asbestos recovered tvas S2.12 per ton of rock mined and hoisted. Fiber classed as crude constituted only li i percent of the asbestos recovered. The output of spinning fiber, including crudes and the liiriiest-grade mill fiber, was 24.415 tons (T.S percent of the gross yield). Figures for other years vary little from those given above.* The average recovery of'fiber from milled rock is about 6 percent. Although Canada produces substantial quantities of spin ning fiber, considerably more than SO percent of its production con sists of the shorter '(consequently, relatively cheap) grades for which, fortunately, an extensive market exists in the United States. The reserves of asbestos in Quebec are very large. Some of the workings are more than 400 feet deep, and core drilling has revealed an abundant supply of fiber, at depths of more than 1,700 feet, as hio`T-hhein fqoullaolwityingas ttahbalet nsehaorwthsethsuerfaacnen.ual production and value of asbestos in Quebec since the industry was first established. ,eduction {shipments and safes} of asbestos in Quebec, 2878-19351 Annual pr .; i Productioo Total value j-- Average value per ton i 1ST*............... 1>79........................ tNVJ............... Ill*e"*V/4............................ IJJl1l11lUSerj6?s589*t1JSfv3fMG17tSo*f3!r2.................................................................................................... ....J 1*97.............. )1I<S$*9Wi0.............................. u39U*2\.................. 1903 ............. 1904.............. IMS............ 1906.......................: ........j} I907................. 50 !. `ici'ooVi300 J 3*0 ( 540 \ 10 I 955 1 U4l * S19.500 24,700 j 35.100 j 52.650 1 6*. 750 75.097 j 141441 !2.440 3.4J* 4.oiv 4.4W 1 9.$fi06.113 J 200.251 | 326,976 I 255.007 426.554 1,270.240 mi..........9.279 { 6.032 ' 6.331 .............7,630 6.756 10.S92 .............13.202 999.STS 390.462 310,156 420. 825 365.175 423,066 399.52S 496.340 25.39315.571 2i.408 561.667 719.416 1.274.315 3146030,634 29.261 . 31479 i 4S.9G0 i 61.675 ?i 1,161. $70 916.970 1.156.970 1.476.450 2.143.653 ir 65.00 'i 1909................ 65.00 }i 1910................ 65.00 W 1911................ 72.00 }: 1912................ G5.SI i 1913................ 55.37 ( 1914................ 59.65 1915................ 49.55 I 1916................ 57.90 1917............... - ` 191&............... 1919......... . 1920............... , 1922...'.'........ I 1923.. 1925................ 1926................ 1925................ 1929............... 1930.............. . 1931.............. . , 1932.............. . 33.43 ! 1933............... 30.16 l! 1934.............. 34.76 l 1935.............. l 61.985 $2,455,919 63.157 2.551.596 64.965 2,296.584 SO. 605 2.667.829 102.224 3.026.306 1 111,175 3.059.084 ! 1 ; J 5 136.609 1U037,.410115! 133.339 137.242 142.375 135.662 3.830.504 2,895.935 3,544,362 5.182,003 7,198. 58 ! 9.019.899 10.932.259 l 179.891 14.749,048 l 87.475 5,199.789 1 160.33? 6.053,068 .! 216,604 7,364.260 .} 20*. 762 6.561.65? 273.522 8.976.645 .i 27S.6S9 10,095.487 .1 274.798 10.621.571 273.033 11.231361 306.055 13.172,551 242,113 S. 390,164 164.297 4,812,886 122.977 151.367 3$..0s3u9,.7t2r?1 155,950 4.936.326 210,467 7.054.614 $39.62 39.16 35.35 33.10 29.60 27.52 25.04 26.96 31.34 31 67 52.45 63.35 SO. 47 81.99 59.44 37.75 33.97 31.37 32.82 36.22 35.65 41.16 43.04 34.65 29.29 24.72 32.90 31.65 33.52 * Ficures lor l*7*-1922Irora The Quebec Asbestos Industry, by Norman R. Fisher: Canadian Min.Jour., Au. 17, 1923. p. 651. Figures (or 1923-35 published by the Quebec Dept, of Colonization, Mines, and Fisheries, Bureau of Mines. Until 1S91, virtually the entire Canadian output was crude fiber, but thereafter both crude and milled asbestos were produced. This change in the character of products is reflected in the sharp drop in average value in 1892 compared with the previous year. The excep tionally high average values from 1918 to 1920 may be attributed to the abnormally high prices obtained for crude fiber on account of war conditions. Crude No. 1. for example, sold for more than 83,000 a tTohnedluarrignegstpaasrbt eosftotshipsropdeuricoedr. in Canada is Asbestos Corporation, T*A nnerating the King'and Beaver pits at Thetford Mines, the foreign I Consolidated at Black Lake, the M Black Lake, the Vimv Ridge s' '->] Broughton, and several other s n The company operates six mills K 500 tons of rock an hour. Bell Ast Turner & Newall, Ltd., of England. Thetford Mines. Johnson's Co., v the pioneer in the district. It open ford Mines and another similar ope) bee Asbestos Corporation, Ltd., cont) facturing Co. of Cincinnati, Ohio, oj Broughton. The Canadian Johnslarge open-pit power-shovel operat from Danville. A mill for treatmi products factory are situated near th Mines, Ltd., operates a pit and mill The mills of the district have a cc tons of rock an hour, and the capital estimated at nearly $22,000,000. The Canadian deposits occupy an e as they are within easy reach'of ex States.* The Quebec industry doubtl indefinitely in the short-fiber market on relatively low-priced products di tion. The future of the spinning-fibt bright because the price per ton of tl it a world-wide market range, and c and Soviet Russia has become increas the writer56 pointed out the danger to States markets of increasing imports < try, but it was not until 5 years late by the industry to meet this compefiti and exercising economies in mi , Such consolidations and cost redu^.,oi try by economic conditions, because wi can competitors the struggle for dir cutting that was carried to a point x reduced to bankruptcy, and the margin panv was extremely small. Since thei fished on a better competitive basis, bi output of Russian mines and the concetion in the hands of one powerful coj still a serious problem for producers i substantial quantities of spinning a.progress toward placing her products r establishing, in 1931, a uniform classify From 19lfi to 1924 some interest in tl industry in Ontario was aroused. Go< tained at two points in Doloro Townshi) area of Porcupine. A maximum prod 891,900 was recorded in 1921. The pla 14Bowles, Oliver, Mineral Industry during 1919 Book Co., New Tork, 1920, pp. 41-42. ASARCO ALV 0006279 ASBESTOS was S2.12 per ton of rock mined and rude -'instituted only 1*4 percent of the tpu spinning fiber, including crudes iber. ..as 24,415 tons (7.8 percent of the . >thsr years vary little from those given ry of fiber from milled rock is about 6 produces substantial quantities of spme than 90 percent of its production conquentlv, relatively cheap) grades for isive market exists in the United States, m Quebec are very large. Some of the feet deep, and core drilling has revealed at depths of more than 1,700 feet, as the surface. rs the annual production and value of industry was first established. and sales) of asbestos in Quebec, 1878-19351 iverago ! value >er ton - Year Produc tion Total value Average value per ton $65.00 65.00 65.00 65.00 72.00 ' 65.61 58.37 39.65 49.55 37.90 69.77 328.32 107.75 64.16 43.99 55.1' 42. 33. 30. Ho 31.23 37.36 33.60 33.70 37.92 31.94 33.43 30.16 34.76 :7........... ;m............ 2909........... `.911............ 1912............ .....1913............ 1914............ 1915............ 1916............ .......... 1917............ 1918............. 1919............. . 1920............ 2921............ 2922............ ...... '923............ *24............ r.25............. .926............ 1927............ .. !93S............ 1929............ 1930 ;93l........... 1932............. 1933............ . . 1934............ ...... 1935............ 61.985 65.157 64.965 SO. 605 102.224 111.175 136.609 107. 401 113.115 133.339 137,242 142.375 135.362 179.391 $7.475 160.339 216.304 208.762 273.522 278.6S9 274.798 273,033 306.055 242.113 164,297 122.977 158.367 155.980 210.467 $2, 455.919 2.551.596 2.296.584 2,667.529 3.026.306 3.059.084 3.830.504 2. 895.935 3.544.362 5.182.905 7.198.538 9.019. S59 10.932.2S9 14.749.048 5.199.759 6.053.068 7,364,260 6.561.659 8.976.645 10.095.467 IQ. 621.571 11.238.361 13.172.581 8.39a 164 4.812.866 3.039.721 5.211.177 4.936.326 r, 0M.au $39.62 39.16 35.35 29.60 27.52 2S.04 26.96 31.34 3s. it 32.46 83.33 50.47 'll. 99 59.44 37.75 33.97 31.37 32. S2 36.22 38.65 41.16 43.04 34.65 29.29 >i r> 3290 31.65 33. S3 sbestos Industry, by Norman R. Fisher: Canadian Min.Jour., published Dj* the Quebec Dept, of Colonttation, Mines, and intire Canadian output was crude fiber, id milled asbestos were produced. This roducts is reflected in the sharp drop in red with the previous year. The excep3 from 19 IS to 1920 may be attributed s obtained for crude fiber on account of 1. for example, sold for more than 53.000 iod. icer in Canada is Asbestos Corporation, ad Beaver pits at Thetford Mines, the FOREIGN DEPOSITS 33 Consolidated at Black Lake, the Maple Leaf between Thetford and Black Lake, the Vimy Ridge at Coleraine, the asbestos mine at East Broughton, and several other smaller mines as the occasion demands. The company operates six mills having an aggregate capacity of 500 tons of rock an hour. Bell Asbestos Mine^ Inc., now owned by Turner & Rewall, Ltd., of England, operates a large mine and mill at Thetford Mines. Johnson's Co., which began mining in 1878, is the pioneer in the district. It operates a large pit and mill at Thet ford Mines and another similar operation at Black Lake. The Que bec Asbestos Corporation, Ltd., controlled by the Philip Carev Manu facturing Co. of Cincinnati, Ohio, operates a mine and mill near East Broughton. The Canadian Johns-Manville Co., Ltd., conducts a large open-pit power-shovel operation at Asbestos, about 5 miles from Danville. A mill for treatment of the ore and an asbestosproducts factory are situated near the quarry. The Ricolet Ashestos Mines, Ltd., operates a pit and mill about 7 miles east of Asbestos. The mills of the district have a combined capacity of over 1.000 tons of rock an hour, and the capital employed in mines and mills is estimated at nearly $22,000,000. The Canadian deposits occupy an exceptionally favorable position, as they are within easy reach of extensive markets in the United States. The Quebec industry doubtless will maintain its advantage indefinitely in the short-fiber market, because high freight charges on relatively low-priced products discourage transoceanic competi tion. The future of the spinning-fiber industry in Canada is not so bright because the price per ton of this type is* high enough to give it a world-wide market range, and competition with South Africa and Soviet Russia has become increasingly severe. As earlv as 1919 the writer -d pointed out the danger to Canadian supremacy m United States markets of increasing imports of African fiber into this coun try, but it was not until 5 years later that active steps were taken by the industry to meet this competition by consolidating companies and exercising economies in mining, manufacture, and marketing. Such consolidations and cost reductions were forced upon the indus try by economic conditions, because with the loss of markets to Afri can competitors the struggle for diminishing trade led to pricecutting that was carried to a point where several companies were reduced to bankruptcy, and the margin of profit obtained by any com pany was extremely small. Since then the industry has fieen'established on a better competitive basis, but with the rapidly increasing output of Russian mines and the concentration of Rhodesian produc tion in the hands of one powerful company, foreign competition is still a serious problem for producers in Quebec whose mines supply substantial quantities of spinning asbestos. Canada made great Ssss toward placing her production a better marketing basis by ishing, in 1931. a uniform classification of asbestos. From 1916 to 1924 some interest in the development of an asbestos industry in Ontario was aroused. Good-quality chrvsotile was ob tained at two points in Doloro Township south of the gold-proclueing area of Porcupine. A maximum production of 172 tons valued ar $91,900 was recorded in 1924. The plant was dismantled later, and * Bowles. Oliver, Mineral Industry during 1919 (chapter on Asbestos): McGraw-Hill Book Co.. New Vork. 1920. pp. 41--42. ASARCO ALV 0006280 34 ASBESTOS no subsequent activity has been reported except the sale of 2 tons valued at $901 in 1926. In 1935 considerable development work was done by the Rahn Lake Mines Corporation, Ltd., of North Bay. Ontario, on a chrysotile deposit near Matachewan, Ontario, Bannockburn Township, about 30 miles southeast of Timmins in the Porcupine gold area. Erection of a mill is contemplated. Occurrences of chrysotile asbestos of good quality have been re ported near Lytton, Revelstoke, and North Kootenav, British Colum bia, but samples from Lytton proved to be weak, brittle amphibole. Although most Canadian asbestos is exported, the manufacture of asbestos products within the country is assuming increasing impor tance. Before 1921 only one company manufactured asbestos prod ucts in Canada; by 1923 there were three plants in Quebec ana one in Ontario; in 1932 there were five plants m Quebec, six in Ontario, one in Nova Scotia, and one in British Columbia: and in 1933, four in Quebec, five in Ontario, and one each in Nova Scotia and British Columbia. Products manufactured in 1932 were valued at $1,067,801 and in 1933 at $757,626, compared with a maximum of $2,301,924 in 1930. Capital employed by the companies operating in 1933 totaled $1,777,975. RHODESIA The growth of the asbestos industry in Rhodesia has been almost phenomenal. From an initial output of only 55 tons in 1908 it reached more than 42,000 tons in 1929. when of all the minerals pro duced in the countrv the value of the output of asbestos was second only to that of gold. Annual production since the beginning of activity is shown m the following table: Annual production of asbestos in Rhodesia. JhOSSS 4o* crW Eg Year Value Short toss Value | Year Short tons Value 190S................ 1906................ 1910................ 1911................ tQ12 1913................ 1914................ 1915................ 1916................ 1917................. 55 272 332 460 290 2.010 6.157 9.562 f) 55w2 1918................. $.574 1919................ 9.79$ 3.320 102n IS. 823 6.397 1921................ 19.S2S 1922. ____ ... 5.224 $.612 11990243................ 20.364 26.141 32.190 1925............... 34.349 99.059 j 1926................ 33.344 189. $90 j 1927................ 33.176 158.684 425.240 459.572 795.698 1928................ 1929 1931......... 626.898 603.423 765.926 726. S35 794.215 1933.......... 1934....... . 1036 i 56.346 836.469 The fiber is of the chrysotile variety occurring in serpentine. It is similar in character and occurrence to that found in Canada and Soviet Russia. There are three producing districts--the Bulawayo, the Victoria (Mashaba), and the Lamagundi, all in southern Rhodesia. Deposits in other localities are known but have not at tained commercial importance. The Bulawayo district is the most important Its largest mine, the Shabani, opened in 1916, is a prolific producer, in prosperous years providing as much as L200 tons of fiber a month. Other im portant mines m the area are the Birthday, the Nil Desperandum, and the Pangani. The Croft mine at Filibusi has attained some importance. foreign ____ vtw^/vgiis LU6 on of a serpentine mass about 1(% The zone of fiber-bearing se "t and a maximum width o'f ai. : from alteration of dunite, probal intrusion. The asbestos veins ai pentine 20 to more than 200 fe- talc schist that forms the footu contact ranges from 25 to 45, in the flat country the dip is onlj extends down the dip to an unki working limit. The fiber, which < wide, is rarely more than 3 inchc tndinal partings occur in most ve: row. The fiber seams generally are continuous for only short Sis short, irregular, overlapping veir. 7,000,000 tons in 1928. For many years the district wa: transportation; 400 wagons and 7 supplies and products many mil- hindrance was overcome when a SomaDula was completed. The earliest Rhodesian produc 46 miles east of Shabani and 26 l cipal mines, the King's and Gatl many years. The fiber is similar i: area. A small production has be in the Lomagundi district more Here flexible and brittle fibers o separation requires a complex mil In Rhodesia the percentage of estimated that 25 to 30 pereerf -'f as spinning grade, whereas ; output is of this grade, 'i....- -ii as these figures indicate, because s 50 and 60 percent of the Canadian in Rhodesia. Highly efficient mills for treati junction with the larger mines, were consolidated under a single placed in a strong competitive po; prosperous. Profits of the larges 1925 to 1927, 25 percent in 1928, in 1930, 5 percent in 1931, 3?-i perc Most of the fiber is exported to Eu of the port of Beira, Portuguese E ness or the region from consumin higher-grade mill fibers are sold, stock are sold principally in Europ poses. Very little Rhodesian asbes stock reaches the American market The advantage of unified control rapidly increasing exports from I i t 7* ASARCO ALV 0006281 SBESXOS ai reported except the sale of 2 tons nent^' -rk 'was done by the Kahn Lake M>rt Ontario, on a chrysotile ario, Bannockburn Township, about n the Porcupine gold area. Erection >estos of good quality have been reand North Kootenay," British Colum-oved to be weak, brittle ampliibole. estos is exported, the manufacture of untry is assuming increasing impor'inpany manufactured asbestos prodvere three plants in Quebec ana one ive plants m Quebec, six in Ontario, British Columbia; and in 1933, four one each in Nova Scotia and British :red in 1932 were valued at $1,067,801 ed with a maximum of $2,301,924 in companies operating in 1933 totaled unxsiA .dustry in Khodesia has been almost output of only 55 tons in 1908 it 11929, when of all the minerals prof the output oi asbestos was second productio'n since the beginning of x table: hesto* hi 3hode.ua. 1908-36 Short 1005 8.57* 9,798 38.823 19.528 34.229 20.364 28.141 34.349 33.344 33,176 V.ijua | J. Year Short tons Value 192S..;............ 39.960 425.240 1 1929 42.634 459.573 1930................. 37.765 70S. -.98 1931................. 24.042 577.699 1932............... 15.766 626.398 1933................. 30.182 US. 423 1934................. 32.214 765.926 1935................. 42.598 726.535 1936................. 56.346 794.315 970.327 1.156,627 1.070.847 3S6.494 197.092 555.993 402.745 646.658 836.469 j 1 * j j j j j I I * -ariety occurring in serpentine. It :ence to that found in Canada and iroducing districts--the Bulawayo, the Lamagundi, all in southern ilities are known but have not at- nost important. Its largest mine, a prolific producer, in prosperous tons of fiber a month. Other imi Birthday, the Nil Desperandum, ine at Pilibusi has attained some FOREIGN DEPOSITS 35 The asbestos deposits of`the Shabani area occur in the central part 0f a serpentine mass about 10% miles long and 1 to 3 miles wide. The zone of fiber-bearing serpentine has alength of 2% or 3 miles and a maximum width of about 200 yards. The serpentine resulted from alteration of dunite, probably under the influence of a granite intrusion. The asbestos veins are best developed in a zone of ser pentine 20 to more than 200 feet thick close to the contact of a talc schist that forms the footwall. In the hills, the dip of the contact ranges from 25 to 45, but where the formation is found jn the flat country the dip is only 5 to 10. The fiber-bearing zone extends down the dip to an unknown distance beyond the practical working limit. The fiber, which occurs in seams as much as 6 inches wide, is rarely more than 3 inches long, because one or more longi tudinal partings occur in. most veins, except those that are quite nar row. The fiber seams generally parallel the dip of the contact but are continuous for only short distances; they consist of a.series of short, irregular, overlapping veins. Ore reserves were estimated at 7,000,000 tons in 1928. For many years the district was handicapped seriously by difficult transportation; 400 wagons and 7,000 oxen were used for conveying supplies and products many miles over poor roads. In 1928 this hindrance was overcome when a 63-mile railway from Shabani to Somabula was completed. The earliest Rhodesian production was in the Mashaba district 46 miles east of Shabani and 26 miles west of Victoria. The prin cipal mines, the King's and Gaths', have been large producers for many years. The fiber is similar in occurrence to that of the Shabani area. *A small production has been recorded from the Ethel mine in the Lomagundi district more than 200 miles north of Victoria. Here flexible and brittle fibers occur closely associated, and their separation requires a complex milling system. - In Rhodesia the percentage of long fiber is relatively high; it is estimated that 25 to 30 percent of the fiber produced may be classed as spinning grade, whereas only about 7.8 percent of the Canadian output is of" this grade. The difference, however, is not as great as these figures indicate, because short fibers that constitute between 50 and 60 percent of the Canadian production are regarded as waste in Rhodesia. Highly efficient mills for treating the fiber are operated in con junction with the larger mines. In 1929 all the important mines were consolidated under a single company. The industry is thus placed in a strong competitive position and before 1930 was highly prosperous. Profits of the largest company were 20 percent from 1925 to 1927, 25 percent in 1928, 30 percent in 1929, H14 percent in 1930. 5 percent m 1931,3% percent in 1932, and 5 percent in 1933. Most of the fiber is exported to Europe and America, chiefly by way of the port of Beira. Portuguese East Africa. Owing to the remote ness of the region from consuming centers, only the spinning and higher-grade mill fibers are sold. Medium grades classed as shingle stock are sold principally in Europe and Australia for building pur poses. Very little Rhodesian asbestos of lower grade than spinning stock reaches the American market. The advantage of unified control was demonstrated in 1931. when rapidly increasing exports from Russia, combined with decreasing ASARCO ALV 0006282 36 ASBESTOS demand throughout the world, threatened the continued prosperity -..of the Rhodeiian industry. Turner & Xewall. Ltd., who control ~ virtually the entire output of Rhodesia as well as a large part of that from the Union of South Africa, negotiated an agreement with Soviet Russia whereby a fair proportion of the Continental market was preserved for each. UHIOH OF SOUTH AFRICA More hinds of asbestos are produced in the Union of South Africa than in any other country in the world. Blue asbestos (crocidolire) is produced in large quantities in the Cape of Good Hope, chrysotile and tremolite are mined in small quantities in Xatal. while three varieties--chrysotile. crocidolite. and amosite--are mined in the Transvaal. As the last two varieties mentioned are produced com mercially in negligible quantities elsewhere in the world, it is inter esting to review the quantities sold in South Africa during recent rears. The following table shows production by kinds. Production of asbestos in the Union of South Africa, by kinds, JS26-3-). in short tons Sind 1926 . Amosite.................... 2.940 Blue asbestos..........j 4.024 Chrysotile...............i 7.133 Total_______ j H.OT7 1927 j 192S 1929 5.093 ! 6.748 4.S73 5.144 12.174 I 12.162 9.260 6.030 17.747 22.140 : 24.054 33.037 1 1930 3.2S1 5.451 10.519 19.281 1931 2.087 3.6M 9.938 15.676 1932 j 1933 j 1934 ! 1935 1.391 ` 2.964 * 7.715 j j3.090 3.225 1 2.S11 9.572 1 11.025 j 4.654 2.495 15. 620 11070 li 15.887 ! 17.593 ! 22.799 _ The output of amosite recorded in the foregoing table is exclu sively from the Transvaal; the blue variety comes principally from Cape Province, with minor quantities from the Transvaal' while the chrysotile originates almost exclusively in the Barberton district of the Transvaal. ' The following table shows annual production, bv Provinces, from 1910 to 1936. Production of asbestos in the Union of South Africa, by Produces, 1310-36. in short tons1 [Cap,ofj Tear !! HGoopode jI j ii j!N"aTtaoltal Value ! Year I Transj raal | Natal i ; Total i 3910>... 1911.__ 1912___ 1913.... 1914___ 1915___ 1916.... 1917___ 1918.... 1910___ 1920.__ 1921__ _ 1922.__ 1923.... 6S0 1.254 1.217 93$ 1.160 Z 083 4.225 2.999 3.204 3.526 3.467 2.991 4.317 10 30 56 407 3.193 631 3.541 1.593 1.392 4.076 ___3 13 3 24 21 28 98 45 62 6 693 1,267 1.220 962 1.190 2.139 4.656 6.220 3.674 3.933 7,112 5.122 4.389 6.393 10.801 20.893 18.882 16.028 20.087 35,899 83.070 S7.364 66.426 114.195 103.067 81.230 121.453 1924.... 1925.... 1926.... 1928.... 1929.... 1930.... 1931.... 1033.... 1934.... 1935.... 1936.... 3,001 2.540 3,093 4,827 5,078 6,030 5.481 3.651 2.964 3.225 2.810 2.420 2.960 4.240 7.241 7.628 10.168 10.104 17.313 ....... 14.097 22.140 16.976 24.054 26.984 13.800 23 ....... 33.037 19,281 12.025 25.676 9.106 12,070 12.662 15.887 14.783 17,593 20.379 22,799 21.646 24,606 110.075 152.115 216.466 343.301 399.550 497.393 340.795 246.583 116.401 197.120 203.033 226.771 V.m E loE its* Irom Asbestos ID the Union of Sooth Africa: Union of Sour j figures tor 1919"36 from statistics of U. S. Bureau of Mines. FOREIGN' DEPOSITS CAPE OF GOOD HOPE The fiber resources of Cape Province mnsi was first discovered between 1803 and (`woolly stone") was proposed by J. 1-. bestos occurs in northern Cape of Good Ho banded ironstones of sedimentary origin st miles south of Priesba northward beyond tance of about 240 miles. The maximum wi< lavender-blue crocidolite occurs in intei that are widely distributed throughout the As the asbestos is derived from folded set and strike, a knowledge of the geology is es pecting and development. The deposits ; Hall.27 Asbestos is obtained from numerous sn large underground mines. The fiber rang inch to 1 or 2 inches in length, rarely atta The proportion of spinning fiber is relative 20 percent of the fiber produced by the lea about 14 percent of that produced in 192 highly siheified, pale brown, semiprecious eye" or "cat!s-eye". occurs in the Hay dis varieties are obtainable in slabs 9 to *12 i: kinds in pieces only one-half to three-fou 9.000 pounds of "tiger-eve" was marketed The Cape Asbestos Co' undertook active 1893 and in 1929 was operating 13 mine consistently successful. A dividend of 1; in 1932 it dropped to 4 percent but recove Many workings have been developed n Kuruman. The'Dominion Blue Asbestos Turner & Newall. Ltd., is an active produc the belt. Amosite and Blue Asbestos "'d. The area is so large and fiber y- a throughout it that reserves are doubtless is difficult, as the nearest railway line if workings. Much study and experiment fiberization and preparation of blue asbi is used extensively in Europe, bur genera with favor in America. It is applied spinning uses. tbaxsvaal CHRYSOTILE Carolina district.--Asbestos was first about 1905 from a deposit of chrysotile lina. In origin and occurrence it is si zona. Cross-fiber veins occupy a 5-foot z lying a diabase sill. The veins parallel to 15 northwest. From 40 to 60 percent sr Hall. A. L.. Asbestos In the Union of South . Survey Mem. 12, 26 ed.. 1930. ASARCO ALV 0006283 ASBESTOS orld, threatened the continued prosperity r. Turner & Nepali, Ltd., who control of Rhodesia as well as a large part of that 1 A' t, negotiated an agreement with lie.i--portion of the Continental market 7 OF SOUTH AFHICA e produced in the Union of South Africa n the world. Blue asbestos (crocidolite) ies in the Cape of Good Hope, chrysotile : small quantities in Natal, while three '.elite, and amosite--are mined in the varieties mentioned are produced comtities elsewhere in the world, it is inter nes sold in South Africa during recent shows production by kinds. Jnion of South Africa-, by kinds, 1936--3.', in short tons 1929 1930 1931 1932 1933. 1934 1935 1 j 9.260 4 6.030 2 > 17.747 ; ' 33.037 3.231 5.451 19.519 a 087 3.651 9.938 1.391 3.090 3.757 2.984 j 3.225 2.511 7.715 { 9.572 11.025 :3.2St | 15.676 1 1Z 070 j 15.5S7 1 17.593 | 4.684 1495 15.820 21799 :orded in the foregoing table is excluhe blue variety comes principally from quantities from the Transvaal, while st exclusively in the Barberton district anm* ' production, by Provinces, from ton of South Africa, by Provinces, 1910-36, short tons1 alue Total j Value a S3 S.882 *>.023 a os? ISS UU 9.-126 <.195 *.057 :.2.io 1925... 3927... 1925... 1929... 1933....: 1934....; 1935___ ` 1930.... 3.001 4.240 2,540 1 7.62S............. iSiaSSh-a- 5.481 | 13.800 I........... 3.651 2.964 . | 12.025 9.100 iI................... 3.225 l 12.662 {........... 2.310 14.7S3 I............ 2.420 ! 20.379 l........... 2.960 | 21,m ........... 7.241 110.075 10.168 152,115 14.097 215.406 22.140 343,301 24.054 399.550 33. OS- 497.393 lO. 2SI ' 140.795 li:Si 246.563 116.401 15. 567 1 197.120 17.593 203.033 22.799 I 226.771 24.606 , i1 aion of South tatistics of V. Africa: Union or South S. Bureau of Stints. Africa'Geol. Surrey i FOREIGN DEPOSITS 37 CAPE OF GOOD HOPE The fiber resources of Cape Province consist of blue asbestos, which was first discovered between 1803 and 1806. The name "crocidolite" ("woolly stone") was proposed by J. F. L. Hausmann in 1831. As bestos occurs in northern Cape of Good Hope in an extensive belt of banded ironstones of sedimentary origin stretching from a point 20 miles south of Prieska northward beyond Kuruman for a total dis tance of about 240 miles. The maximum, width is about 30 miles. The lavender-blue crocidolite occurs in interbedded cross-fiber veins that are widely distributed throughout the entire length of the belt. As the asbestos is derived from folded sediments with variable dip and strike, a knowledge of the geology is essential to intelligent pros pering and development. The deposits are described in detail by Asbestos is obtained from numerous small pits and from several large underground mines. The fiber ranges. from less than one-half inch to 1 or 2 inches in length, rarely attaining a length of 4 inches. The proportion of spinning fiber is relatively high. Hall55 states that 20 percent of the fiber produced by the leading-company in 1917 and about 14 percent of that produced in 1929 was spinning grade. A highly silicified, pale brown, semiprecious variety, known as "tigereye" or "caris-eye"', occurs in the Hay district. The lighter-colored varieties are obtainable in slabs 9 to 'l2 inches long, and the darker kinds in pieces only one-half to three-fourths inch across. In 1935. 9.000 pounds of "tiger-eye" was marketed. The Cape Asbestos Co. undertook active mining north of Prieska in 1S93 and in 1929 was operating 13 mines. Its"activities have been consistently successful. A dividend of 15 percent was paid in 1923: in 1932 it dropped to 4 percent but recovered to 6 percent in 1934. Many workings have been developed northward to points beyond Kuruman. The Dominion Blue Asbestos Mines, Ltd., a subsidiary of Turner & Newall, Ltd., is an active producer in the northern section of ..the belt. Amosite and Blue Asbestos. Ltd., is another recent producer. The area is so large and fiber veins are distributed so generally throughout it that reserves are doubtless very great. Transportation is difficult, as the nearest railway line is 100 to 130 miles from the workings. Much study and experimentation have been devoted to fiberization and preparation of blue asbestos, with the result that it is used extensively in Europe, but generally it has not been regarded with favor in America. It is applied to both spinning and non- spinning uses. TRANSVAAL CHRYSOTILE Carolina district.--Asbestos was first produced in the Transvaal about 1905 from a deposit of chrysotile 20 to 25 miles east of Caro lina. In origin and occurrence it is similar to that found in Ari zona. Cross-fiber veins occupy a 5-foot zone of altered dolomite overlying a diabase sill. The veins parallel the bedding, which dips S= to 15" northwest. From 40 to 60 percent of the fiber"marketed is over - Hall, A, L., Asbenos la the Union of South Africa: Union of South Africa Geoi. Survey Mem. 12. 2d ed.. 1930. wall, A. L,, Work cited, p. S7. i I ASARCO ALV 0006284 38 ASBESTOS 1 inch long: that less than one-half inch long is rejected. Mines hare been operated at various times, but production has never been large. A second deposit of chrysotile in the Carolina district occurs on the farm Kalkloof, 3 miles south of the Komati River and 47 miles by road from Carolina. This occurrence is of the usual type--cross-fiber veins in serpentine derived from ultrabasic igneous rock. The fiber occurs in many closely spaced, parallel thin seams inclined at a steep angle. The asbestos is of good quality, but a large proportion of it is short mill fiber. Evidently reserves are extensive. A mill was in operation in 1929, but production has been small. Barberton district.--In 1918 Hall59 directed attention to a chryso tile deposit near Barberton in eastern Transvaal, but serious develop ment aid not take place until after 1921. The deposit occurs in a belt of serpentine bounded by quartzites lying about 3 miles from Kaapsche Hoop and 14 to 17 miles by road from Godwin River station. The asbestos-hearing portion of the serpentine has been traced for a length of 3 ana a width of 2 miles. Further exploration may ex tend its boundaries considerably. Underground mines have been de veloped extensively near both the eastern and western ends of a 2-mile zone containing large reserves of fiber. The New Amianthus Mines, Ltd. (subsidiary of Turner & Newall, Ltd.), operates near the western end. Here the most productive fiber belt is known as the "ribbon rock" or "ribbon line." In a typical sec tion. the upper 7 feet contains narrow parallel fiber seams so nu merous and closely spaced that the fiber content mav run as high as 40 percent of the entire rock mass. Beneath this band is a 6-foot mass of serpentine, in which the chrysotile veins are fewer and thicker, providing fiber up to 6 inches long. Figure 6 shows the abundance of fiber veins. The veins dip 10 to 20. The fiber is of high quality and is easily separated from the massive serpentine. Records for one. period show that fiber recovered from the upper beds amounted to 30 percent of the rock mined, while from the lower beds it was 10 percent or less. In 1930. the average recovery for the mine was 15 to 17 per cent. In that year about 8 percent of the output was of spinning grade, and 92 percent was classed as shingle stock. The mine is a steady producer, furnishing about 1,000 tons of fiber a month in 1930. The Munnick-Mvburgh mine occupies the eastern end of the ser pentine area. The fiber seams are more or less parallel and resemble those at the western end already described. Thin seams are close to gether, and the thicker seams are more widely spaced. A majority of the seams worked range from one-sixteenth to one-half inch in width. Operations began about 1920, and in 1930 the mine was pro ducing about 200 short tons of fiber a month. For some years the products of the mines were transported 18 miles to Godwin River station in wagons hauled by oxen or mules. The completion in 1929 of a 5.9-mile aerial tramway over a 2,000foot escarpment to Elandshoek made possible a reduction in haulage cost to about one-eighth of the amount formerlv paid. From tins point the asbestos is carried by a short-rail haul to Lourenco Mar ques, Portuguese East Africa, the port of shipment. The extent of the area, the' high percentage of fiber of superior quality in the rock, and the easy access to a seaport make the Bar-* * Hall. Jl L., Asbestos In the Union o South Africa: Union of South Africa Geoi. Survej- Mem. 12,1918, p. 59. ASARCO ALV 0006285 Ku.i.iik .Uln-Mus V.IIIM III llm New A m l.iitilm s M im a . M i l , li.irlw rti.ii t lU r lr l, T rim sviiu l, S o itlli A filu t. ASBESTOS one-half inch long is rejected. Mines hare mes, but production lies never been large. the Carolina district occurs on the tth .-^-Jie Komati River and 47 miles by occurrence is of the usual type--cross-fiber from ultrabasic igneous rock. The fiber d, parallel thin seams inclined, at a steep ood quality, but a large proportion of it is y reserves* are extensive. A mill was in action has been small. 918 Hall " directed attention to a chrysoin eastern Transvaal, but serious developil after 1921. The deposit occurs in a belt uartzites lying about 3 miles from Kaap5 by road from Godwin River station. The f the serpentine has been traced for a f 2 miles. Further exploration may ex.-ably. Underground mines have been de:h the eastern and western ends of a 2-mile res of fiber. les, Ltd. (subsidiary of Turner & Newall, ;tern end. Here the most productive fiber i rock" or "ribbon line." In a typical secrains narrow parallel fiber seams so nu:hat the fiber content may run as high as mass. Beneath this band is a 6-foot mass ; chrysotile veins are fewer and thicker. ?s long. Figure 6 shows the abundance of Y to 20. The fiber is of high quality and le massive serpentine. Records for one ered from the upper beds amounted to 30 liile from the lower beds it was 10 percent e rec'-rerv for the mine was 15 to 17 perl pe : of the output was of spinning classes as shingle stock. The mine is a about 1.000 tons of fiber a month in 1930. line occupies the eastern end of the ser ais are more or less parallel and resemble eady described. Thin seams are close to ns are more.widely spaced. A majority from one-sixteenth to one-half inch in bout 1920. and in 1930 the mine was proof fiber.a month. lucts of the mines were transported 18 ion in wagons hauled by oxen or mules, a 5.9-miie aerial tramway over a 2,000oek made possible a reduction in haulage the amount formerly paid. From this 1 by a short-rail haul to Lourenco Mar:a. the port of shipment. he higu percentage of fiber of superior easy access to a'seaport make the Bar- nlon of South Africa: Union of South Africa Oeot. r j i ; : ; ASARCO ALV 0006286 FOREIGN DEPOSITS 39 berton district on of the most important asbestos centers in the world. The development of mines in this region is reflected in the rapid increase in production of the Transvaal, beginning in 1923, as shown in the table of production in the Union of South Africa by Provinces. AMosirn This unique variety of asbestos occurs most prominently near Penge, about 30 miles north of Lydenburg in northeastern Trans vaal. The belt extends from the_ Steelpoort River northwestward along the basin of the Olifants River, thence westward to Chuniespoort. The asbestos occurs in cross-fiber veins interbedded with sili ceous ferruginous slates associated with intrusive diabase sills. The principal mines, the Egnep and Amosa, about iy2 miles apart, are situated near Penge. Fiber is obtained from surface workings and from several levels underground. A number of smaller mines and open-pit workings have been operated in the western part of the belt near the ilalips River. The fiber veins show remarkable con tinuity over long distances, and reserves are extensive. The most notable feature of the asbestos is its length, which attains a maximum of approximately 11 inches and averages about 6 inches for the commercial product. When the material was first marketed difficulties were encountered, because standard equipment for manu facturing asbestos products was not well adapted for fiber of such great length. With subsequent adjustments, the material was pre pared extensively for spinning, magnesia pipe covering, and manu facture of other asbestos products. The future of amosite is uncertain. The claim is made that the relatively large production recorded for 1928 and 1929 was stimu lated chiefly by a shortage of chrysotile. As a similar shortage is unlikely to occur asain for many years, future activity in' the amosite fields will depend primarily on the serviceability of this type of fiber. CBOCIDOLITS Crocidolite occurs in the western part of the amosite belt, a region designated as the Petersburg district. It is associated closely with amosite, both varieties being obtained from some of the workings. The blue asbestos is obtained chiefly from open pits near and east of the Malips River. The maximum length or fiber is about 3 inches. Production never has been large. In 1928, the last year for which it was recorded, the output was 66 tons. AN-nTOPRTT.T-TTC Anthophyllite occurs in the Zoutpansberg district. 50 miles west of Waterpoort Siding. The fibrous structure has evidently been de veloped under the influence of weathering. therefore the persistence of usable fiber at depth is doubtful. Asbestos taken from pits not exceeding 30 feet deep was used some years ago for boiler covering, but there'has been little recent production. NATAL The most important asbestos deposit in Natal is in the Tiurela River Yallev east of Kranz Kop, Zululand. Chrysotile asbestos occurs here In vertical cross-fiber veins near contacts of aplite dikes ASARCO ALV 0006287 40 ASBESTOS with green serpentine. Most- of the fiber is short and inferior. .Pro duction since 1910 has ranged from 2 to 62 tons a year. A deposit of brittle tremolite asbestos has been worked near the ~Klip Hirer. 45 miles from Dundee, a region where transportation is very difficult. The small amount of material obtained was used for the manufacture of asbestos brick and for insulation. OTHER AFRICAN OCCURRENCES Asbestos has been reported at various other points in Africa, Thefiber occurs in Bechnanaland. Kvasaland, ana in serpentine in the northwest corner of Swaziland. The latter deposit is evidently not far from the productive Barberton district of the Transvaal. Anthophvllite occurs at Morogoro in what was formerly German East Africa, and chrysotile was reported near Macequece, Portuguese East Africa, in 1929. SOVIET RUSSIA Before the World War. Russia ranked nest to Canada as an as bestos-producing country. During the revolutionary period the- in dustry was almost at a standstill, but since then it has been revived on an extensive scale. The following table shows production since 1913. The figures were obtained from the annual chapters on asbes tos in Mineral Resources of the United States, published by the United States Geological Survey until 1924 and thereafter by the United States Bureau" of Mines, and from the corresponding chapters in the Minerals Yearbook, published by the Bureau of Mines. Year Asbestos production in Russia, IQ1J-36 [f Metric tons Vear 1913.......... 1914......... .................. I 3913.................................! 1916.......... ........... *--| 1917........ ................ 1919.. 1520.. * 1921., 15.691 . 1922... ............... 1923........ ............. 8.192 : 1924......................... (<1>).478 = m6....................1 **................................ I 2,H 3.213 **54..7<8360 112.330 '26. <92 > Data oot available. 7 Year ended Sept. 30. The great increase since 1929 does not- affect- world markets as much as might be expected, because increasingly large quantities are used for home consumption. According to recent figures,50 the percentage of Russian asbestos exported dropped from 51.1 in 1922-23 to only 20.5 in 1931. This condition reflects the rapidly expanding manu facture of asbestos products in Soviet Russia. However, these figures tell only part of the story, for they do not indicate the percentage of spinning and higher-grade mill fibers exported. The 50 to 80 percent of the production remaining in the country may consist largely of the shorter fibers, which are of minor importance m world trade. The asbestos region providing the major part of Russian production comprises what is known as the Bajenova district in the Urals. Prin- * Economic' Review of the Soviet Union, Oct, 15,1932, p. 383. FOREIGN DEPOS1 cipal production is at Asbest. about 90 kil< lovsk (Ekaterinburg). Minor productioi from the Alapaevsk area in the north "ic the northwest. The largest mine r Outside the Bajenova dTstrict the on.c Minusinsk, on the Yenisei River in easten border. Here the deposits, said to be of as those- of Arizona, have been worked in 1.490 tons being reported in 1905. Ashesin various parts of the Altai Mountains _A chrysotile asbestos deposit on the L: trictof the. Caucasus. about 98 kilometers been described.51 The mineral occurs : have been intruded by granite. In gene from 2 to 7 mm, with a maximum of 25 n is said to be of good quality, but the res deposit has been worked in'a small way opment is anticipated. A small output was reported from tl 1907 to 1909. Chrysotile has been reported ir. othe Ini a peridotite-serpentine belt in the Pn e_rjn Siberia; on the upper course of the ' near the source of the Kuban River Turkestan. At Asbest. in the Bajenova district, now centered. 20 or more oper. pits under control of the State since 1918 : Uralasbest Trust since 1921. Asbestos 1710. and systematic development urn began in 18S5. The asbestos-bearing s 21 mlometers long and 200 to 1.200 mettites. which are bounded by schist or s on the east. The asbestos is cor.*' 5 tine, some of which attain a lens f feet The highest percentage o: asbes of these masses. The cross-fiber vein.1 with a vertical dip. Slip fiber appe: usually is regarded as being higher i but Ru Kevser52 has pointed out th; ferric iron, whereas in the Russian J This probably accounts for the grt asbestos upon weathering. Russian r tively shallow overburden and are t sivelv, which mav account for the s condition of the fiber compared with ring below the 50-foot level more n Quebec. While the percentage of s posits is a little higher than that in total commercial fiber is about the s: ttTatarinov. P., Tbe Laba (Bedeni Deposit casus: Neues Jabrb. Mineral. Geol.. Referate IX * Ru Keyset, A., Chrysotile Asbestos in and Min. Jour., August 1033, p. 33S. ASARCO ALV 0006288 ASBESTOS of the fiber is short and inferior. Proed frn*n 2 to 62 tons a year, tolii bestos has been worked near the Dunnes,- a region where transportation is nount of material obtained was used for brick and for insulation. erican OCCURRENCES 1 at various other points in Africa. The td, Kyasaland, ana in serpentine in the inch The latter deposit is evidently not Barberton district of the Transvaal, irogoro in what was formerly German ras reported near Macequece, Portuguese TVTET RUSSIA lussia ranked next- to Canada as an ashiring the revolutionary period the inistill," but since then it lias been revived following table shows production since ned frorn the annual chapters on asbes* the United States, published by the rvey until 1924 and thereafter by the s, and from the corresponding chapters -.Wished by the Bureau of Mines. "'tion ill Rutfin. 19l.J-.7G >ar : .......................! ------- ` --------- .......... ............ Metric tons i j Year i t 2.604 * 3,213 : *4.780' * 8.456 8 1929................ 1930...................... ........ 1931........ 1932............... 1934.................. !M3........................ Metric tons *29.320 54.083 -54.6*4 59.800 71.700 92.200 95.300 .: Year ended Sept. 30 does not affect- world markets as much increasingly large quantities are used ding to recent figures.30 the percentage Iropped from. 51.1 in 1922-23 to only reflects the rapidly expanding manu3oviet Russia. However, these figures :hey do not indicate the percentage of fibers exported. The 50 to SO percent the country may consist largely of the '.or importance in world tracle.' ;the major part of Russian production Bajenova district in the Urals. Prin- . Oct. 15.1032. p. 365. i i FOREIGN DEPOSITS 41 cipal production is at Asbest, about 90 kilometers northeast of Sverd lovsk fEkaterinburg). Minor production in this district is obtained from the Alapaevsk area in the north and from the Keviansk area in the northwest. The largest mine in the latter is the Kramouralsk. Outside the Bajenova district the only notable production is from Minusinsk, on the Yenisei River in eastern Siberia near the Mongolian border. Here the deposits, said to be of the same general character as those of Arizona, have been worked in a small way, a production of 1.490 tons being reported in 1905. Asbestos also occurs in serpentine in various parts of the Altai Mountains southwest of Minusinsk. A chrysotile asbestos deposit on the Laba River in the Maikop dis trict of the Caucasus, about 98 kilometers from a railway, has recently been described.51 The mineral occurs in veins in serpentine which have been intruded by granite. In general, the fibers range in length from 2 to 7 mm, with a maximum of 25 mm (10 inches). The asbestos is said to be of good quality, but the reserves are not extensive. The deposit has been worked in a small way since 1930 and a larger devel opAmesnmt aisll aonutitcpiuptatweads. reported from the Katun River district from 190C7htroys1o9t0il9e. has been reported in other parts of Russia, as follows: In a peridotite-serpentine belt in the Province of Transbaikalia, south ern Siberia: on the upper course of the Yenisei River in the far north: near the source of the Kuban River east of the Crimea: and in TuArkteAstsabne.st. in the Bajenova district, where the asbestos industry is now centered, 20 or more open pits are worked. They have been under control of the State since 1918 and have been operated by the Uralasbest Trust since 1921. Asbestos was first discovered here about 1710. and systematic development under direction of Baron Girard began in 1885. The asbestos-bearing serpentinized intrusion is abouc 21 kilometers long and 200 to 1.200 meters wide. It consists of peridotites, which are bounded by schist or slate on the west and by granite on the east. The asbestos is confined to ellipsoidal masses of serpen tine, some of which attain a length of 3,500 feet and a width of 1,000 feet. The highest percentage ot asbestos is found in the central parts of these masses. The cross-fiber veins generally run north and south with a vertical dip. Slip fiber appears in places. Russian asbestos usually is regarded as being higher in iron than the Canadian fiber, but Ru Keyser33 has pointed out that Canadian asbestos is high in ferric iron, whereas in the Russian fiber ferrous iron predominates. This probably accounts for the greater discoloration of the Ural asbestos uponweathering. Russian asbestos deposits have a compara tively shallow overburden and are therefore weathered quite exten sively, which mav account for the somewhat harsher and less silky condition of the fiber compared with the Canadian. Asbestos occur ring below the 50-foot level more nearly resembles that obtained in Quebec. While the percentage of spinning fiber in the Russian de posits is a little higher than that in the Canadian, the percentage of total commercial fiber is about the same. "Tatarinov. F.. The Laba (Bedeni Depoalt of ln ,ho N"r`' "Tatarinov. P.. The Uta (BMMI ' 1036 do 240-250. l.v'ilev'ai1 w' A`"chrrioUla- Lbe.toa In'the Bajenova District, L\ S. * i: t::u. _ tl... t.xfiier n oHS. ASARCO ALV 0006289 42 ASBESTOS r FOREIGN DEPOSIT Extensive and systematic core-drilling' indicates a reserve for the entire Bajenova district of more than 3.000.000 metric tons of fiber " within 50 feet of the surface. This estimate is based on only a 2-per cent recovery: with a probable -P^-percent recovery this quantity would be more than doubled. As the deposits extent! far below the 50-foot level it is apparent that the reserves are very great. The reserves of asltestos in the Soviet Union were estimated on Januarv 1.1934. at 19,400.000 tons. Much of the upper rock is soft enough to be mined with picks and shovels. Before the revolution, crude methods of mining and fiber recovery were practiced, and only the longest grades of fiber--crudes, spinning, and shingle stock--were recovered. However, with in creased mechanization and development of markets for the shorter grades, most of the fiber in the rock mined is now separated and sold. As the flow of water is heavy below the 50-foot level, the workings consist, principally of broad, shallow, open pits, although some under ground development has taken place. A narrow-gage railway was built from Asbest to Bajenova (34 km) in 1927. making possible more intensive development. There are three major groups of mines in this district. The most northerlv. known as the "Proletariat", produces shorts almost exclu sively. 1The two major producing groups are the October (central) and the Ilvinski (southern). Several mills with very crude equip ment have been operated for many years. Since 1931. newer and more efficient mills have been built 'and new equipment has been installed in some of the old ones. A large asbestos-products industrv has been established in.Russia, and crudes and spinning fibers which in former years constituted a large part of the output have been supplemented by mill products similar to those produced in Canada. itaiy ' Italy is called "the cradle of the asbestos industry", because the mining of asbestos and the manufacture of its products began on an industrial scale in that country. Italy also is unique in that much of the fiber produced in early ye'ars consisted of tremolite. a variety of amphibole asbestos little'used elsewhere. Before discovery of'the Canadian deposits, Italy was the chief source of supply of'asbestos for both Europe and America. After the Quebec deposits were developed, the Italian industrv* experienced little growth. Produc tion from 1898 to 1934 is shown in the following table: Annual production of asbestos in Italy, 1S9&-1934. in metric tons Year Toes i 1 Year Toes Yeer Tons 1898................................. 1899............. .................. 1900................................. 1901................................. 1902................................ 1903................................. 1904................................. 1905................................. 1906................................. 1907................................. 2908................................. 1909................................. 1910................................. l 131 1911................................ 81 1912................................ 126 1913................................ 243 1914........................... 243 1915................................ 202 1916............................... J82 1917............. v>o lOifi . 209 1919 ... 359 1920. . . 359 1921 . 190 1922 ........... 175 1923.--................ 170 169 175 in 163 82 85 60 9S 165 420 540 1.538 192.V . 1913... .. ... . 2.160 2.105 2,900 3.840 4.950 2.847 851 632 1.284 3.267 2,252 One important deposit is in the Susa Torino near the French border. Here tr particularly well-adapted to the mani'-^cti an the mountains S.Ut/0 to 9.000 feet a' is along the Aosta Valley near Ivrea m i 40 miles front Turin. Tremolite asbestt mountains in this locality since 1805. but t since 1905. The fibers are long and hi heat, but owing to the difficulty of sepa well-adapted to weaving. A tliird sotu asbestos is near Sondrio'in northern Lon is a long-fibered variety similar to that ol The Balangero mine' situated in Torinof Turin has"been the chief producer du bestos of this district- is ehrysotile, the 2.000 tons in 1925 and nearly* 5.0uu tons ; production. In 192S. modern mechanics troduced. The fiber is said to be iuferio spinning purposes. It commands prices ton and is used chiefly for the manufact Asbestos was produced in Sardinia i ported in Corsica. Italy is both an importer and an expo all the fiber required for textile use *ai the shorter grades are imported, while bestos and other uonspinnmg grades ar CTPE.US The chief asbestos deposits of Cyprus Troodos in the west-central area. J largely of olivine is altered to serpent' fiber ehrysotile asbestos occurs in the that have a maximum tliickness.of boi shearing evidently have exerted .45 of the fibrous structure. The a.-t^ios 1 to 2 percent. The deposit, is widen tiou on reserves is available. The fiber is of the ehrysotile variei spinning, but small shipments of sp 1934. Milled fiber is graded into tlirei fines. The standard grade, designat comprise about 90 percent of product About 1925 an aerial ropeway IS ' conveying the asbestos from Amian The construction cost was about 2.: porting asbestos by means of the i investment and complete amortizatio was given as 6s. 9d. a ton. whereas m formerly* employed on the 37-mile wi The industry attained considerable but thereafter'the demand fell off gn ations were conducted at a substantu recovered greatly in following years ASARCO ALV 0006290 T ASBESTOS core-drilling indicates a reserve for the more .than 3.000.000 metric tons of fiber T `stimate is based on only a 2-perable --70-percent recovery this quantity I. As the deposits extend far below the that the reserves are very great. The oviet Union were estimated on January soft enough to be mined with picks and ion, crude" methods of mining and fiber only the longest grades of fiber--crudes, c--were recovered. However, with inlevelopment of markets for the shorter le rock mined is now separated and sold. 7 below the 50-foot level, the workings shallow, open pits, although some under- :en place. A narrow-gage railway was ova (34 km) in 1927, making possible ups of mines in this district. The most netariat", produces shorts almost exclu ding groups are the October (central) Several mills with very crude equipr many years. Since 1931. newer and Jn built and new equipment has been ies. A large asbestos-products industry 1, and crudes and spinning fibers which a large part of the output have been ts similar to those produced in Canada. ixaiT of the asbestos industry", because the amU '".ire of its products began on an 7. . 7 also is unique in that much of jars consisted of tremolite, a variety of d elsewhere. Before discovery of" the the chief source of supply of asbestos ica. After the Quebec deposits were ry experienced little growth. Produewn in ihe following table: in Itain. in metric tons Toes -j Ve*r 170 ,J 1921. 169 j 1925........... 175 ! 1926........... i7i i 1927........... 163 > 1923........... b* 1 1929........... $5 1930........... 60 1931........... 98 f 1932........... 165 1933........... 420 i 1934............ M0 1 .53S 5 Tons 1160 2.103 2.900 3.540 < 4,930 2.347 S31 1,34 3,267 2.252 I I I FOREIGN DEPOSITS 43 One important deposit is in the Susa Valley region of western Torino near the French border. Here tremolite asbestos, which is particularly well-adapted to the manufacture of acid filters, is mined in the mountains 8.000 to 9.000 feet above sea level. A second deposit is along the Aosta Valley near Ivrea in northeastern Torino, about 46 miles from Turin. Tremolite asbestos has been mined in the mountains in this locality since 1365. but there has been little activity since 1905. The fibers are long and highly resistant to acids and heat, but owing to the difficulty. of separating them, they are not well-adapted to weaving. A third source or supply of "tremolite asbestos is near Sondrio"in northern Lombardy. This asbestos also is a long-fibered variety similar to that of the 'Torino deposits. The Balangero mine" situated in Torino about 20 kilometers north of Turin has-been the chief producer during recent veal's. The as bestos of this district is chrysotile, the output of which was about 2,000 tons in 1925 and nearly 5.000 tons in 1923, the year of greatest production. I11 1928. modern mechanical mining equipment"was in troduced. The fiber is said to be inferior to Canadian chrysotile for spinning purposes. It commands prices ranging from $75 to $150 a ton and~is used chiefly for the manufacture of artificial stone. Asbestos was produced in Sardinia in 1926. and deposits are re ported in Corsica. Italy is both an importer and an exporter of asbestos. Practically all the fiber required for textile use and considerable quantities of the shorter grades are imported, while small quantities of filter as bestos and other nonspinning grades are exported. criRtrs The chief asbestos deposits of Cyprus occur at Amiandos. on Mount Troodos in the west-central area. A peridotite plug consisting largely of olivine is altered to serpentine on the periphery. Shortfiber chrysotile asbestos occurs in die serpentine in irregular veins that have a maximum thickness of about one-haif inch. Faulting and shearing evidently have exerted a definite influence on development of the fibrous structure. The asbestos content of the rock rims only 1- to 2 percent. The deposit is evidently extensive, but no informa tion on reserves is available. The fiber is of the chrysotile variety and generally too short for spinning, but small shipments of spinning fiber were reported in 1934. Stilled fiber is graded into three classes--standard, shorts, and fines. The standard "grade, designated "shingle stock", is said to comprise about 90 percent of production. About 1925 an aerial ropeway IS miles long was constructed for conveying the asbestos from Afiiiandos to the seaport at Limasol. The construction cost was about 2.320 a mile. The cost of trans porting asbestos by means of the. ropeway, including interest on investment and complete amortization of the equipment in 10 years, was given as 6s. 9d. a ton. whereas motor-wagon or animal transport formerly employed on the 37-mile winding road cost 20 to 25s. a ton. The industry attained considerable importance from 1926 to 1929, but thereafter"the demand fell otf greatly. It is reported that oper ations were conducted at a substantial loss in 1932, but the industry recovered greatly in following years. ASARCO ALV 0006291 44 ASBESTOS FOREIGN DEPOSITS Production lias been in the hands of a single company. The Cyprus Asbestos Co.. Ltd., operated for several years prior to 1927. AUSTRALIA ~hux in that year the Cyprus Trading Corporation. Ltd., was organ 'WESTSLS AUSTRALIA ized ami absorlied the former company. In 1932. the newer firm was reorganized :ts Cyprus General Co.! a British organization, and in 1930 the assets of tite hitter company were acquired by the Tunnel Asbestos Cement. Ltd., a subsidiary of The Tunnel Portland Cement Co. of West Thurrock. England. The asbestos is used by the com pany for manufacture of asbestos-cement products in England. As there are no local asbestos-products plants, the entire output is exported, principally to European countries. Exports began in 1906. Figures for tonnage and value of exports over a period of years are shown in the following table: The most important recent develop it the Sherlock property, in the Roebourne from the port of Balia Balia. Here chr reins that are restricted to a relatively veins, sbejpj&aurtautceud. buyj a dolerite dike, have ' of 1,0rv0\0n feet. 'TT'Vhiqe pneorTcpepn'ntraftfgrpe. noff ffiibhperr 92, iiln to be much higher than in the principal world, and is of good quality. Up to 193* had been mined by contract laborers ant no systematic mining had been followed Asbestos exported from Cyprus. 1922-3G [ erection of a pumping plant were started : Other producing areas are Lionel in t Veer j Lon? tons . Value 1 ' Year ; ! Lon? tons Value ! Year ; Long j tons !* Value Soansville and Cooglegong in the Marbl posits are all in the Pflbarra Goldfield ai tile occurs in veins up to 30 inches wide w; 1922.............; 1922.............: 1924............. 1925........... 11*26.............. i 2.2*5 2.115 i A 372 i 3.390 ` k 3J1 22.599 ; 1927..............! 57.155 : 192S..............: SO. 070 1929............. M. 639 1930............. 12!. *57 1931............. 10.90; 207.562 ; 1932............. 11.579 231.692 || 1933............. . 13.79$ ` 292,971 l! 1931..............j 5.400 116.092 \i 1935..............! 3.571 - 66.381 {( 1936..............i 1.600 ! 4.604 7.590 7.514 * 9,500 1 27.214 ` 44. OSS ` 73. 562 50.174 SO. 313 of 6 inches. The veins have beer, proved Fiber from this area shipped to London > lo 150 a ton. Asbestos was discovered in the Marble * Reported by Cyprus A General Asbestos Co.. Ltd. deposit has been reported 15 miles west veins range from threads up to G inches Of the fiber exported during 1934. 2.589 tons were reported as destined for the United States. The following table compiled by Elf< Western Australia for a period of years. The following table, taken from the Annual Report of the Insjiector of Mines and Labour. 1934. indicates the scope of recent operations and the ratio of fiber to rock. Hock mined, rock treated, and fiber produced in Cyprus, 19S1SJ). in long tons Production of asbestos iu IVesten Year Quantity/ ; tons Value, i Locality where turned Year Socle RilDOU......... flock treated............... Asbestos fiber produced.............. .................... .................. .... 1931 113.73S 25.966 1.13S 1932 155.765 36.819 1,520 1933 1931 -- 351.178 76.7S4 3.494 711.016 153.865 7.0SI l 19211........ 1 202 32 12.221 Lionel. 1.360 Cooglegong. 1927... I 1922......... 1 K 2.5 7,350 Lionel. 250 Cooglegong. 1923......... 1924......... 1925......... 1926......... , 1 ; : 1 Ill 733 50 91 i* 3.865 150 2.206 1.C19 2.436 292 Lionel. Cooglegong. Lionel. Do. Do. Roebourne. 1930.. 1931.. 1932.. 1 OTHER FOREIGN DEPOSITS Asbestos deposits of minor commercial importance at present are covered in the following pages, by countries, arranged in alphabetical order. ARGENTINA Deposits of asbestos are reported at Alta Gracia, Cordoba; Sierra de la Cortadera. Mendoza; Fiambala. Catamarca; and in the Prov inces of San Luis and San Juan. The fiber is said to be too short for spinning or weaving and production has been very small. The only available figures show an output of about 42 short tons in 1926 and of less than a ton in 1927. SOUTH AUSTRA A promising deposit of crocidolite ocf about 248 miles north of Adelaide. magnesian limestone. The maximum inches, but most of the asbestos is shoi feet apart have been sunk to a depth a drift. Unfortunately, the ore body and nothing is known of its cominuatii curs as bunches and veins in dolomitimiles from Adelaide. It is said to " Elford. Harold S.. Australian Nonmetalllc M Min. Review, vol. 25. Sept. 5, 1933, p. 396. 1343,2*--37------ { ASARCO ALV 0006292 ASBESTOS die hands of a single company. The operated for several years prior to 1921, Ti ur Corporation, Ltd., was organr co. _Jiv. In 1932. the newer firm was leral Co.." a British organization, and in companv were acquired by the Tunnel sidiarv or The Tunnel Portland Cement and. "The asbestos is used by the comistos-cement products in England, os-produets plants, the entire output is jean countries. Exports began in 1906. e of exports over a period of years are 'ed from Cyprus, 1928-38 J Long j tons Value j Year -! 10,904 11.579 : 13,796 * 5.400 ; 3.371 207.562 1932.......... 31.692 1933............. 292,971 1 1934 116.092 1 1935........... 66.38L 1938.......... . Ltd. Lon; tons Value 1.600 4.604 7.314 9.306 ! 27.214 *44. ass * 73.562 50.174 SO, 343 S 1934, 2.S89 tons were reported as :rom the Annual Report of the In1934. indicates the scope of recent to rock. produced in Cyprus, 1931-34, in long tons ; 1931 1932 1933 ....................... 25,966 155.765 36.519 1.520 354,178 76.7S4 3.494 1934 711.646 1S3.S65 7.081 SIGN DEPOSITS nmercial importance at present are . countries, arranged in alphabetical ed at Alta Gracia. Cordoba: bala. Catamarca; and in the The fiber is said to be too duction has been very small, eput of about 42 short tons ii FOREIGN DEPOSITS 45 AUSTRALIA WESTERN AUSTRALIA The most important recent development in Western Australia is the Sherlock property, in the Roebourne district, about 24 miles from the port of Balia Balia. Here chrysotile asbestos occurs in veins that are restricted to a relatively narrow zone. Two main veins, separated by a dolerite dike, have been proved for a length of 1,000 feet. . The percentage of fiber 2 inches long and over is said to be much higher than in the principal producing regions of the world, and is of good quality. Up to 1934, about 1,000 tons of fiber had been mined by contract laborers and shipped to Europe, but no systematic mining had been followed. Shaft sinking and the erection of a pumping plant were started in 1934. Other producing areas are Lionel in the Xullagine district, and Soansville and Cooglegong in the Marble Bar district. These de posits are all in the Pnbarra Goldfield area. At Soansville chryso tile occurs in veins up to 30 inches wide with a maximum fiber length of 6 inches. The veins have been proved over a length of 1.200 feet. Fiber from this area shipped to London commanded a price of 120 to 150 a ton. Asbestos was discovered in the Marble Bar area in 1909. A large deposit has been reported 15 miles west of Cooglegong. Chrysotile veins range from threads up to 6 inches wide. The following table compiled by Elford, " shows production in Western Australia for a period of years. Production of asbestos in Western Australia. 1921-32 Quantity.! .......... i Locality wber l| tons , *"' j mined j .. `Mr !quntity.i j tons j j Locality wbero I mined 1921.... 202 IZ 221 Lionel. 1922.... * 32 179 1.360 Cooglegon;. 7.350 Lionel. i 2.5 250 Cooglegon*. 1923.... 111 3,865 Lionel. |3 150 Cooglegong. 1924-- 73 2.206 Lionet. 1925.... 50 1.619 Do. 1928.... 91 2.436 Do. j 14 292 Roebourne. i 1927............ 1923............. 1929 1930........ i 1 1031 1 1932............. 10.3 11.7 191 63 -65 17 108 110 304 732 8.568 6.113 4.223 500 1.446 1.762 Lionel. Soansville and Lionel. Sherlock. Soansville. Pilbarra. West Pttbarra. Roebourne. Do. SOUTH AUSTRALIA A promising deposit of crocidolite occurs 10 miles north of Hawker, about 248 miles north of Adelaide. Apparently it is derived from magnesian limestone. The maximum length of" the fiber is about 2 inches, but most of the asbestos is short and matted. Two shafts 40 feet apart have been sunk to a depth of 26 feet and connected with a drift. Unfortunately, the ore body is faulted at the 26-foot level, and nothing is known of its continuation. Bluish gray crocidolite oc curs as bunches and veins in dolomitic limestone at Robertstown, S3 miles from Adelaide. It is said to have excellent heat-insulating ** Elford. Harold S.. Australian Xonmetalllc Minerals. Min. Review, vol. 25. Sept. 5. 1933, p. 396. 134342*--3T------- 1 IL Asbestos: Chem. Eng. and ASARCO ALV 0006293 46 ASBESTOS qualities. Other occurrences hare been noted at Kapunda, Truro. --Blount Baker, Gumeracha. and 'IVilliamstown. Chrysotile of good quality occurs at Mimbric near Cowell. Veins attainin': a maximum width" of 2 inches appear in serpentine travers ing marble. According to report, the asbestos-bearing rock would yield 0.5 percent crude and 15 to 20 percent mill fiber. "Annual pro duction ranging from 5 to 21 tons has been noted in South Australia for various years. QUEENSLAND Asbestos has been noted in many localities in Queensland, mainly within the serpentine belt northeast and north of Rockhampton, ex tending from Balnagowan near the Fitzroy River to Marlborough. The deposits at Prinehester and Marlborough appear to be the mostimportant, though little is yet- known of their quality or extent. A small amount of fiber has been mined, and it is reported that it sold for 25 a ton. On Marlborough Creek near its junction with the Fitzroy River well-defined veins having a maximum fiber length of 114 inches are reported. Queensland asbestos is said to be coarse in texture and of low strength. It is well adapted for asbestos-magne site flooring, for boiler covering, and as an ingredient of paints. . NEW SOUTH WALES A chrysotile-asbestos deposit was worked in a small way near Barraba for several years following 1916. Short-fiber chrysotile occurs in a belt of serpentine about *4 niile wide. The area is greatly faulted, which makes mining difficult. A small mill, similar to those in Quebec, was operated for a time, and fiber recovery is said to have been 5.75 percent of the rock treated. Crocidolite occurs near Gundagai and Broken Hill, but the percentage of recoverable fiber is said to be low. TASXAZtU. An occurrence of asbestos at Beaconsfield was discovered more than 30 years ago. a production of 200 tons being recorded in 1899. It is of the chrysotile variety, occurring in irregular and noncontinuous veins in a serpentine belt 2 miles long and 1*4 miles wide. The fiber rarely reaches 1 inch in length; commonly, ft is y8 inch long. The asbestos-bearing area is not very large, 'and the veins so far un covered are too scattered and irregular to encourage deep working. A limited production of asbestos of fair quality is possible. The fiber has a higher iron content than Canadian asbestos. A mill for ore treatment was erected in 1917, but very little fiber has been produced. A promising deposit of asbestos in* serpentine is reported on the. western shore of Macquarie Harbor, 16 miles south of Strahan. It is undeveloped. AUSTRIA Sliort-fibered ampliibole, known as "microasbestos", is mined in Austria near the Hungarian frontier. It is mixed with both asphalt and concrete used for road surfaces.- brazil An amphibole-asbestos deposit is reported near Rio Branco, Per nambuco, and asbestos of uncertain type occurs in Minas Geraes. 'St-. *i FOREIGN DEPOSITS BULGARIA Amphibole asbestos of the anthophy]]jte area in the eastern Rhodope Mount a* i production of several hundred tons wa_ _ china Asbestos said to be of the chrysotile vari Provinces in China, including Chihli. Jehol Szechuan, Hupeh, and Kwangtung.' The are in the Laiyuan district, Chihli {Hopeh "Hopei" in th*e footnote reference is not nasbestos occurs in numerous generally plimestone. Maximum fiber length is abou has evidently resulted from metnniorphis; limestone under the influence- of granitesimilar in origin to the Arizona deposit: described by Hou." Reserves in the an tons. The longer grades are of spinning been worked since 1914. Production in The fiber is conveyed on horseback to Yi from there to Tientsin by train. It suppl the latter city. Four such plants were rej nets are mostly for domestic consumption Japan. Asbestos mines about- 5 miles from Ch: worked in a small way for more- than 20 shipped to factories at Osaka and Tokyo. CZECHOSLOVAK According to the Bureau of Foreign a sole producer of asbestos in the country Verwertung von Asbest Gesellschaft m. ' of 2,600 metric tons in 1935, 2,100 i < reported. No data are available a.~ product, nor has the Bureau of Mines : bestos occurrence in this country. FINLAND Asbestos production is confined to a east-central Finland, where 1.000 to r were mined annually until recent yen dently increased. According to a Brit Jopson, production in 1934 was 14.0C 9,200 tons in 1933 and 6.000 tons in 1! reported by Borgstrom36 Finnish asbc cal composition: SiO,. 56.57; Al-Os, CaO, 0.57; H-0+, 4.89; H-.O-. 0.14. **Hon, T- F,, Notes on the Asbestos Deposit English): Nat. Geol. Surrey China Geoi. Bull. 1 u Bureau of Foreign and Domestic Commerce, Apr. 15.1936. p. 9. * Borgstrfim, L. H., Finnish and Foreign Ashe ASARCO ALV 0006294. .asbestos irrences have been noted at Kapunda, Truro icha. and \VHliamstown._ . jualirv occurs at Mimbnc near Cowell. Veins wid f 2 inches appear in serpentine travers- ig ^ rzport, the asbestos-beanng rock would and 15 to 20 percent mill fiber. Annual pro. j to 21 tons has been noted in South Australia QTOWSLANB ted in many localities in Queensland, mainly elt northeast and north of Rockhampton, ex;-an near the Fitzroy River to Marlborough, ster and Marlborough appear to be the most is yet known of their quality or extent. A is been mined, and it is reported thac it sold -Iborough Creek near its junction with the ed veins having a maximum fiber length of Queensland asbestos is said to be coarse in gth. _ It is well adapted for asbestos-magneivering, and as an ingredient of paints. SEW SOUTH WALES -posit was worked in a small way near Barilowing 1318. Short-fiber chrysotile occurs about h mile wide. The area is greatly mg difficult. A small mill, similar to those or a time, and fiber recovery is said to have ock treated. Crocidolite occurs near Gunt the percentage of recoverable fiber is said Tasmania 5 at Beaconsfield was discovered more than of 200 tois being recorded in 1899, It is iccu g in irregular and noncontinuous milt, -onz and 1*4 miles wide. The fiber igth: commonly, it is y8 inch long. The it very large, and the veins so far unnd irregular to encourage deep working, estos of fair quality is possible. The fiber than Canadian asbestos. A mill for ore .7, but very little fiber has been produced, isbestos in serpentine is reported on the Harbor. 16 miles south of Strahan. It is .vtstrja known as "microasbestos", is mined in frontier. It is mixed with both asphalt trfaces. BRAZIL iosit is reported near Rio Branco. Perertain rvpj; occurs in Minas Geraes. FOREIGN DEPOSITS 47 BULGARIA, Amphibole asbestos of the anthophyllite type occurs over a large .rea in the eastern Rhodope Mountains of southern Bulgaria. A ,reduction of several hundred tons was reported unofficially in 1933. CHINA not now rccugiiu<Lu; asowiv^ ..umo w ...-- B___ ally parallel cross-fiber veins in limestone. Maximum fiber length is about 1% inches. The asbestos has evidently resulted from metamorphism of a siliceous magnesian limestone under the influence of granite intrusions, therefore it is similar in origin to the Arizona deposits. The deposits have been described by Hou.34 Reserves in the area are estimated at 400,000 tons. The longer grades are of spinning quality. The deposit has been worked since 1914. Production in 1927 was 130 metric tons. The fiber is conveyed on horseback to Yiksian (106 kilometers) and from there to Tientsin by train. It supplies manufacturing plants in the latter city. Four such plants were reported in 1927. Their prod ucts are mostly for domestic consumption, though some are shipped to JapAasbne. stos mines about 5 miles from Chinchu, Manchuria, have been worked in a small way for more than 20 years. The output has been shipped to factories at Osaka and Tokyo, Japan. CZECHOSLOVAKIA According to the Bureau of Foreign and Domestic Commerce," the sole producer of asbestos in the country is "Asbest" Gewinnung und Verwertung von Asbest Geseilschaft m. b. H. at Dobsina. An output of 2,600 metric tons in 1935, 2,100 in 1934, and 11200 in 1933 has been reported. Ho data are available as to the nature or quality of the product, nor has the Bureau of Mines any previous record of an as bestos occurrence in this country. FINLAND Asbestos production is confined to a locality in Tuusniemi Parish, east-central Finland, where 1.000 to 1,500 tons of amphibole fiber were mined annually until recent years, when production has evi dently increased.^ According to a British report on Finland by Keith Jopson, production in 1934 was 14,000 metric tons, compared with 9200 tons in 1933 and 6.000 tons in 1932. According to an analysis reported by Borgstrom38 Finnish asbestos is of the following chemi cal composition: SiO-, 56.57; Al.Oj, 1.02; FeO, 5.72: MgO, 30.73; CaO. 0.57; H-0+, 4.89; HjO--, 0.14. This corresponds closely with 54 Hou, T. F., Notes on the Asbestos Deposit of Laiyuan District. Hopei Province in EacBllsuhre)a: uNoeft. FOoeroeli.gnSuarnvdeyDCohmineasticDeCool.mBmuelrl.ce2,5F. oMreairgcnh M10e3ta5l.spapn. d Minerals: Cite. 3, Apr*.BXnor.z1s0tr3d8m. .p.L0. . S., Finnish and Foreign Asbestos : Tefc. _Foten. Finland Fdrb., vol. S.*. ASARCO ALV 0006295 48 ASBESTOS the analysis of Georgia anthophyllite shown on pace 4. The prod uct of the mines, together with imported chrysodie fiber, is used in a factory at Helsingfors for the manufacture of asbestos board, Etemit. tiles, packings, clothing, and gloves. A small quantity of actinolite has been mined in northern Finland. FRANCE Although France uses large quantities of asbestos in its manu facturing"plants, a very small production of raw fiber has been re corded. It is interesting to note, therefore, that plans have been made to open an asbestos quarry in the Chateau-Ville-Vieille-etChateau-Q.ueyras Commune in the Guil Valley at an altitude of about 2.000 meters." A deposit of asbestos in Corsica was reported in 1921. GERMANY Discovery of a greenish white chrysodie in Baverischer Wald. East Bavaria, was reported in 1935. This is said to be the only asbestos occurrence known in the country and is exceedingly important from the German standpoint because of increasin'! demands for home con sumption. Imports of raw fiber to supply German asbestos-products plants increased from 7.582 tons in 1932 to 20.154 in 1934. INDIA The Hassan district of Mysore State has been the most productive area in India. Both chrysodie and amphibole fibers are available. A maximum production of over 1,700 long tons was obtained in 1920, but no output has been, recorded since 1929. A small production has been noted from Seraikela State, Bihar and Orissa from 1921 to 1932. The material is evidently tremolite. Asbestos occurs in many other parts of India; but no estimates of reserves are available and none of the deposits seems capable of a large production of highgrade fiber. The development of a substantial asbestos-producing industry in India will depend largely upon the establishment of domestic asbestos-products plants that will absorb the short fibers. The following table, compiled from data assembled by Coulson," shows production from 1906 to 1934. Aabcatoa production m India, i>06-$4 Year Lone tons Value Year Lone tons Value Year Lone tons Value 1006........... 20.6 1908_________ | 18.0 1910--..... 3.0 1914______ 5.0 1916______ 5.0 3917____ - 148.0 1918______ 357.0 1919______ .... 388.0 6 2223 303 965 1.439 1920._____ 1921...___ 11992232_.________ 1924______ 1925____ _ 1926______ 1927........... X. 818.0 7.272 1925.. 315.5 8S4 1929.. 242.0 701 1930.. 247.0 659 1931.. 125.3 1,354 1932------------- 16.0 361 1933___ ...... 65..78....47......1...0.71.8.16.. ..1..9...3...4...........l 156.5 318.4 23.2 96a.00 1.622 1.206 5 677 24.6 1 27. 1B9u3r5e.apu. o4.f Foreign and Domestic Commerce. Foreign Trade Notes: YoL 4, no. fi. May Coulson. A. L.. Asbestos In the Ceded Districts of the Madras Presidency: With Notes on Its Occurrence In Other Parts of India: Mem. GeoL Survey of India, voL 64, pt. 2.1034, p. 249. FOREIGN DEPOSITS IRELAND An asbestos deposit at Avoca. County tv.Vfc 1931. Xo data are available on variety, i MEXICO An unusually good sample of mountain cork matted, amphibole asbestos--was obtained by in 1931 from an undeveloped deposit near San ing to report, surface exposures indicate that tos has also been reported from the State of P NEWFOUNDLAND A deposit of chrvsotile asbestos discovered thought to represent a continuation of the Qu available as to its quality or extent. NEW ZEALAND Chrvsotile asbestos in veins as wide as 3 in tine area at least 3 miles long near Moun Takaka district of Xew Zealand. Both cro?.* available. The cross-fiber veins occur princ inches thick surrounding cores of massive se veins. The fiber yield of the shells is estim; The deposit evidently is extensive and is un< PHILIPPINE ISLANDS A deposit of amphibole asbestos occurs i; Luzon Island. A considerable quantity wt pipe covering and similar uses. In 1936 the Bureau of Mines received s this deposit, which, upon examination, prove strength and flexibility. Some of it ">b spinning fiber, although it is not as s' g asbestos. Xo data are available as to me deposit. PORTUGAL Asbestos of uncertain quality, probabl; extent, is reported from two places in the Alemtejo, southern Portugal. Xo product SPAIN Two occurrences of chrvsotile asbestos 1920--one in the Pyrenees and the other tains. A production of 165 metric tons w but no later activity has been noted. SWITZERLAND Asbestos occurs in the Cantons of Gr Graubunden, Switzerland, but production about 400 tons was obtained under the 1919. The most important deposits are ASARCO ALV 0006296 3X0S lite shown on page 4. The prod)or+.'-J chrysotile fiber, is used in a ifa. .j of asbestos board. Eternit s. a small quantity of actinolite >'CE antities of asbestos in its manuduction of raw fiber has been re- therefore, that plans have been in the Chateau-Ville-Vieille-ete Guil Valley at an altitude of was reported in 1921- ant ysotile in Bayerischer Wald. East ais is said to"be the only asbestos nd is exceedingly important from increasing demands for home consupply German asbestos-products 1932 to 2CU54 in 1934. IA tate has been the most productive .d amphibole fibers are available. 00 long tons was obtained in 1920, ice 1929. A small production has Bihar and Orissa from 1921 to imolite. Asbestos occurs in many ater * reserves are available and. e o. large production of higha substantial asbestos-producing rgelv upon the establishment of tKat" will absorb the short fibers. >m data assembled by Coulson," L in India. 1006-3$. `..on? vons Value ; Year Lon? tons Value S1B.0 315.5 242.0 247.0 125.3 16.0 58.4 67.7 7 272 ~ *S84 Ttji; 659 ; 1,354 361 ; 786 : 1.011 . 1923................. 1929_________ loan.... 1931_______ _ 1039. . 1Q33................. 1Q-U. 136.5 318.4 33.2 6.0 90.0 1.622 1,206 $8 5 677 24.6 :e. Foreign Trade Notes: Yol. 4. no. 3. May Districts of the Madras Presidency: With ndia; Mem. OeoL Survey of India, voi. 64, foreign deposits 49 IRELAND a*testos deposit at Avoca, County Wicklow, was reported in 19<J1. No data are available on variety, qualitv, or extent. MEXICO An unusually good sample of mountain cork--a variety of spongy, matted, amphibole asbestos--was obtained by the Bureau of Mines in 1931 from an undeveloped deposit near San Luis Potosi. Accord ing to report, surface exposures indicate that it is extensive. Asbes tos has also been reported from the State of Puebla. NEWFOUNDLAND A deposit of chrysotile asbestos discovered near Port au Port is thought to represent a continuation of the Quebec belt. No data are available as to its quality or extent. NEW ZEALAND Chrysotile asbestos in veins as wide as 3 inches occurs in a serpen tine area at least 3_ miles long near Mount Arthur in the upper Takaka district of New Zealand. Both cross fiber and slip fiber are available. The cross-fiber veins occur principally in shells 6 to 30 inches thick surrounding cores of massive serpentine with few or no veins. The fiber yield of the shells is estimated at 10 to 25 percent. The deposit evidently is extensive and is undeveloped. PHILIPPINE ISLANDS A deposit of amphibole asbestos occurs in Ilocos Norte Province. Luzon Island. A considerable quantity was mined about 1920 for pipe covering and similar uses. In 1936 the Bureau of Mines received samples of asbestos from this deposit, which, upon examination, proved to be chrysotile of fair strength and flexibility. Some of it probably could "be classed as spinning fiber, although it is not as strong as Canadian or Arizona asbestos. No data are available as to the extent or location of the deposit. PORTUGAL Asbestos of uncertain quality, probably in deposits of limited extent, is reported from two places in the Beja district. Province of Alemtejo. southern Portugal. No production is recorded. SPAIN Two occurrences of chrysotile asbestos in Spain were reported in 1920--one in the Pyrenees and the other in the Cantabrian Moun tains. A production of 165 metric tons was recorded for that year, but no later activity has been noted. SWITZERLAND Asbestos occurs in the Cantons of Grisons, Tessin, Valais, ami Graubunden. Switzerland, but production is small; a maximum of about 400 tons was obtained under the war stimulus of 1913 and 1919. The most important deposits are at Poschiavo, Canton of ASARCO ALV 0006297 50 ASBESTOS Grisons. where a small amount of chrysotile of spinning quality is available. Both chrysotile and treniolite are said to occur in Graubunden. TURKEY' A small quantity of asbestos has been produced near Kutaia. west ern Turkey. An output of 58 tons was recorded for 1032. with a value of about 24 a ton. Very promising samples of cross-fiber chrysotile were obtained by the Bureau of Mines in 1934 from a deposit, said to occur near Sarikamis, Province of Kars. Turkish Armenia. The samples indicated that the percentage of fiber to rock runs very high and that a fair proportion of crude asbestos is obtainable. No" details as to the extent of the deposit or its availability are known. VENEZUELA A deposit of chrysotile asbestos apparently of good quality occurs about 8 miles from Tinaquillo. State of Cojedes. about 145 miles from Caracas. The nearest railhead is Valencia.-40 miles distant, and the nearest seaport is Puerto Cabello. 65 miles away. ' The occurrence is unusual, as the fiber is associated with clay and shattered rock. A little development work has been done and 'small shipments have been made, but much systematic exploratory work must be conducted before the commercial value of the deposit can be determined. OTHER COUNTRIES Asbestos occurrences have been reported in Bolivia: Gorbea. Chile: Chosen (Korea). Japan; Madagascar: Spitzenbergen: and near Alexandretta. Syria. POLITICAL AfTO COMMERCIAL CONTROL Russia only of the four leading producing countries has im portant asbestos-products manufacturing plants. The other prin cipal producing countries--Canada, Rhodesia, and the Union of South Africa--utilize a very small proportion of the asbestos they produce. On the other hand, the principal' asbestos-consuming countries--the United States, England, France. Germany. Belgium, and Japan---produce no asbestos, or only small tonnages. A dartre proportion of all asbestos mined, therefore, enters international trade, and all the principal nations are interested in foreign sources of supply and their availability in times of emergency. POLITICAL CONTROL Three of the four large asbestos-producing countries of the world-- Canada. Rhodesia, and the Union of South Africa--are in the British Empire. Moderately important deposits in Cvprus and Australia and small deposits in India, New Zealand, and Newfoundland also are under British political control. The largest deposits outside the. British Empire are those of the Soviet Union, while others of considerable importance are under the dominion of the United States, Italy, and Finland. Relatively small deposits are controlled politically bv Argentina. Austria, China, Czechoslovakia. Spain, Switzerland, 'Turkey, and Venezuela. INTERNATIONAL COMMERCIAL Ct All asbestos-producinc companies tr are controlled by United States c: 1 Commercial control of the Cana^ar. company. Asbestos Corporation. Ltd., nadian. and United States capital. Ji operator, probably is controlled by ( Asbestos Corporation. Ltd., owned'bv ine Co.. Cincinnati, Ohio: the Canacli subsidiary of Johns-Manville. Inc.. N bestos Mines. Ltd., a New York firm.; capital. The Bell Asbestos Mines. Ii Mattison Co.. Ambler. Pa., is now c Ltd., London. England. The ovnersi therefore, evidently is divided amon Canadian capital. The amounts of c: the United States are approximately investment is less. British capital predominates in a' panies of Rhodesia and the Union of The Soviet Union controls, both activities in the asbestos industry of t: The one company operating'in C capital. For many years a British company tion of Italy*, but since 1929 an Ita! Balangero Mines, where the chief prc Practically all the deposits if Aust or Australian capital. INTERKATION-f The United States is the larger ~o and imports over 95 percent of u cent of Canadian production enters tl proximity to the extensive United S distinct advantage over all other com For many years England. France. G most of their supplies from Canada. England's needs. Other European c quantities from Russia, and fluctu; Canada and Africa. EXPORTS FROM PRINCIPAL A recent report- from Irving X. L in Johannesburg, shows the distribui try of destination during 1934 and 1 exports from the Unioifof South A in 1935 about 52 percent of the tot United Kingdom, nearly 22 percen and the remaining 26 percent to cot United States received less than 5 pt siderably more per ton than any otl ASARCO ALV 0006298 ASBESTOS mt hrvsotile of spinning quality is and .xeuiolite are said to occur in TCTtKET 5 has been produced near Kutaia. west58 tons was recorded for 1932, with a Very promising samples of cross-fiber the Bureau of Mines in 1934 from a ;arikamis, Province of Kars. Turkish cated that the percentage of fiber to it a fair proportion of crude asbestos to the extent of the deposit or its KyEZmOA stos apparently of good quality occurs lo, State_ of Cojedes. about 145 miles ailhead is Valencia,-40 miles distant, ?rto Cabello. 65 miles away, is the fiber is associated with clay and opment work has been done and small ut much systematic exploratory work commercial value of the deposit can :r cocnthies en reported in Bolivia: Gorbea. Chile: adagascar: Spitzenbergen; and near COI-r-'ERCIAL CONTROL eadii.s producing countries has immfacturing plants. The other prinanada. Rhodesia, and the Union of small proportion of the asbestos they d. the principal asbestos-consuming England, France. Germany, Belgium, :os, or only small tonnages. A large i. therefore, enters international trade, are interested in foreign sources of in times of emergency. CAT CONTROL os-producing countries of the world-- jn of South Africa--are in the British it deposits in Cyprus and Australia 'ew Zealand, and Newfoundland also rol. the British Empire are those of the onsiderable importance are under the Italy, and Finland. Relatively small ally by Argentina. Austria. 'China, land, Turkey, and Venezuela. I INTERNATIONAL TRADE 51 COMMERCIAL CONTROL All asbestos-producing companies in the United States apparently are controlled by United States capital. Commercial control of the Canadian mines is diverse. The largest company, Asbestos Corporation, Ltd., is controlled by English, Ca nadian, and United States capital. Johnson's Company, the pioneer operacor, probably is controlled by Canadian capital. The Quebec Asbestos Corporation. Ltd., owned'bv the Philip Carey Manufactur ing Co., Cincinnati, Ohio; the Canadian Johns-Manville Co., Ltd., a subsidiary of Johns-Manville, Inc., New York; and the Nicolet As bestos Mines, Ltd., a New York firm, are dominated by United States capital. The Bell Asbestos Mines, Inc., operated by the Keasbey & Mattison Co., Ambler, Pa., is now controlled by Turner & Newall, Ltd., London! England. The ownership of the Canadian companies, therefore, evidently is divided among English, United States, and Canadian capital. The amounts of capital invested by England and the Uniced States are approximately the same, while" the Canadian investment is less. British capital predominates in all the asbestos-producing com panies of Rhodesia and the Union of South Africa. The Soviet Union controls, both politically and commercially, activities in the asbestos industry of the Urals. The one company operating in Cyprus is controlled by British capital. For many years a British company controlled most of the produc tion of Italy", but since 1929 an Italian company has operated the Balangero Mines, where the chief production is now centered. Practically all the deposits if Australia are controlled by English or Australia'u capital. INTERNATIONAL TRADE The United States is the largest consumer of asbestos in the world and imports over 95 percent ot its supplies. Normally TO to 75 per cent of Canadian production enters the United States. Because of its proximity to the extensive United States markets, Canada enjoys a distinct advantage over all other countries in the field of short fibers. For many years'England, France, Germany, and Belgium imported most of their supplies from Canada. Africa now furnishes much of England's needs. Other European countries are securing increasing quantities from Russia, and fluctuating supplies are obtained in Canada and Africa. EXTORTS PROM PRINCIPAL PRODUCING COUNTRIES A recent report from Irving N. Linnell, American consul general in Johannesburg, shows the distribution of African asbestos by coun try of destination during 1934 and 1935. The following table shows exports from the Uniotrof South Africa. It may be observed that in 1935 about 52 percent of the tocal quantity was shipped to the United Kingdom, nearly 22 percent to other European countries, and the remaining 26 percent to countries outside or Europe. The United States received less than 5 percent of the total, but paid con siderably more per ton than any other country, due to the fact that ASARCO ALV 0006299 52 ASBESTOS the United states imports from this source onlv tlte hi<rher-<rrade fibers. Exports of asbestos from the Cnion of South Africa. 1934 and 1935 i Shore tons iI i Vi;:ed Kizfiom................................................................... 1 Er.7;um.................................................................................. Germany................................................................................. Hoihod..........................................................................."... S. 662 559 1.023 m 366 Value : Short tons | 113.019 7,625 17.301 16.860 7.107 12.284 1.124 1.195 1.493 455 Value 135. no 10.737 17.335 26.351 7.672 Sweden.................................................................................... Denman:.................................................... PortuMl.................................................................................. lipu................................................... tciredSu:,;.................................................... Canada.................................. ... . Australia.................................................................. India.................................................. 1rueuav................................................ Argentine................................................................... 60 1.327 715 9 1.692 2S9 73 24 13.884 133 24.133 1. "3* 043 Estimate. The following table shows similar data for Rhodesia, but the fig ures are somewhat uncertain because a large percentage of the fiber Is shipped through Portuguese East Africa and the ultimate destination is unknown. Evidently^ percent or more of the 1935 exports reached European ports. The'small figures recorded in this table for Euro pean countries outside of the United Kingdom indicate that most or all of their requirements of Rhodesian fiber are included under Portu guese East Africa or Optional Ports. Only about 3 percent of the shipments reached the United States. However, that shipped to the United States averaged about $145 a ton, whereas European ship ments averaged about $90 a ton. Exports of asbestos from Rhodesia. 1934 and 1933 1934 1936 j Short tons Value Short tons! Value Vnited Einrdom........................... .. Australia*.................................................. India......... ......................................... Portugese East Africa ................................... Japan..................................................... Dutch East Indies............................. Vnited States.................................... Union of Eouth Africa >............................. Holland......... ..................................... Italy....................................................... Germany____________ ________ ____ Belgium............................................. Sweden_____ -........................................... Optional Ports}_......................................... 11.764 1.100 850 15.396 1.721 47 1,076 154 27 2 5 46 222.014 20.051 11.625 291. S30 26.515 423 24.276 1.665 384 34 60 567 13,120 1.450 780 19.02$ 1,076 50 97 1,418 366 206.995 26.437 11.986 335.254 23.743 682 97 i 40.955 3.968 600 7,305 9,552 132.193 t Most of that enterics Portuguese Bast Africa is destined to the Continent of Europe, but ultimate country of destination is unknown at time of shipment. * Probably for resbipment, but destination unknown. * Destined lor Continent of Europe, butultimate country of destination unknown. INTERNATIONA^! As indicated in the following table o: 50 percent of the total is consigned to countries, Japan, and. during recer' stantial buyers. The decline in e: a may be due to the pronounced expans pro'ducts manufacturing industries, wh tities of the raw asbestos produced. E> to the United States as shown in this t figures for imports into the United St by the Bureau of Foreign and Domes crease in Russian production has not as might be expected, because Russif asbestos-products-manufacturing indu; of its raw material in its own plants. Exports of asbestos from V. S. t (Complied by B. B. Valdbauer. Foreip Country of destination Mirrlr Czechoslovakia................................... 1 5 1. U. 3 3 . i , . * 1 j 3: i As given in Foreign Trade (Vnesbnayo Torgoviya) Si i During these years 1 ruble was worth about ST cents. The following table shows exports try of destination, in 1934 and 1935. arid 58 percent in value of the totr United States. In 1935, the figures tively. Exports from Canada to th table differ only by a small amount f Canada into the United States as coi and Domestic Commerce. The tra> is relatively small, because the price a heavy transportation expense. ASARCO ALV 0006300 OS 3 source only the higher-grade >t &. --.Africa, 1934 and 1935 1931 1935 Short tons 1 Value J Short tons | Value l S. 652 559 3,028 903 1.139 824 50 113.019 7.625 17.301 16.560 7,107 20.362 7.938 726 1,327 * 15 9 1,692 289 73 24 23.195 13.884 133 24.133 1 4 4 4 925 447 12.2S4 1.124 l, 195 1.493 455 666 250 5 2,301 1,114 26 2.206 298 253 24 10 133.736 io. nr 17.335 26.381 7,672 12.652 3.641 119 39 30.497 23,043 369 29.775 1.317 3.562 * 447 199 data for Rhodesia. but the fig. large percentage of the fiberIs ica and the ultimate destination .lore of the 1935 exports readied corded in this table for EuroICingdom indicate that most or fiber are included under Portu- Only about 3 percent of the However, that shipped to the . to" -hereas European ship- idesia,' 1934 and 1935 1934 i 1933 1 hort tons Voiue 1 Short toos Value 11.764 | 1.100 t a 50 15.395 1.721 47 1,076 1M 2 5 46 212.014 VJ.Uol 11.625 2*1.330 26.515 423 24.276 1.665 334 34 60 567 13.120 1.450 7S0 19.023 1,075 97 1,418 366 000.995 26.437 11.986 335.254 23.743 971 40.955 3. VriS 600 1 7.305 ! . 9.552 aed lo lie Continent of Europe, but ultimate * c/ destination unknown. 7 iIn>TtEeRrNnAaTtIiOoNnAaLl tTrRaAdDeE 53 As indicated in the following table of exports from Russia, nearly 50 percent of the total is consigned to Germany. Other European countries, Japan, and, during recent years, the United States are sub stantial buyers. The decline in exports in 1935 compared with 1934 may be due to the pronounced expansion in the domestic asbestos- products manufacturing industries, which consume increasing quan tities of the raw asbestos produced. Exports of asbestos from Russia to the United States as shown in this table do not check closely with figures for imports into the United States from Russia as compiled by the Bureau of Foreign and Domestic Commerce. The great in crease in Russian production has not affected world trade as much as might be expected, because Russia is developing an important asbestos-products-manufacturing industry and thus uses a great deal of its raw material in its own plants. Exports of asbestos from U. S. S. R. (Russia),' 1934-35 (Compiled by B. B. Waldbauer, Foreign Miner*! Service Division] Country of destination 1934 1935 Metric tons Rubles * Metric tons Rubles * Netherlands.............................................................. . Sweden............I....................................... ------ Switzerland................................................ .......... Cmted Kinedom....... ............................................. Total. 136 3,565 410 104 43 1.045 14.741 3.464 3.550<it 147 74 268 771 16 1.647 3.040 566 19.000 336.000 43.000 10.000 6.000 109.000 L492.000 379.000 310.000 200 18.000 9.000 11.000 25.000 80.000 6.000 SCO 149.000 192.000 53.300 3,2*8.000 44 1. SSL 72 15 944 12.018 1.562 ! 2.417 1 4 118 15 690 j 14 | 1.453 1 3.099 | 463 | 25,109 6.000 139.000 5.000 1.000 $4,000 1.255.000 l<7.000 146.000 1.000 10.000 2.000 60.000 1.000 148.000 181.000 <1.000 i \s ejren in Foreign Trade (Vneshaayo TorgovJya) Statistical Summary, Moscow. * During these years 1 ruble was worth about 87 cents. The following table shows exports of Canadian asbestos, by coun try of destination, in 1934 and 1935. In 1934, 71 percent in quantity and 58 percent in value of the total exports were destined to the United States. In 1935. the figures were 77 and 66 percent, respec tively. Exports from Canada'to the United States as given in this table' differ only by a small amount from the figures for imports from Canada into the United States as compiled by the Bureau of Foreign and Domestic Commerce. The trans-Atlantic trade in short fibers is relatively small, because the price obtainable is too low to justify a heavy transportation expense. ! ASARCO ALV 0006301 54 ASBESTOS Exportx nt asbestos from Canada. 1934-351 [Compiled by B. B. V.'aldbsuer. Foreipn .Mineral Service Dlvulosl 1934 Country of domination Fiber -_____________ . Sand and wa5te . Ii Total Australia................. ' .chrt t<*n> j w*! j jValue J Short tons Value s Short tons 1 msw i 1----------------- France..................... German?................................. Italy.TM............................... Japan.................. Netherlands........................ Spain....................... I. cited Kingdom............... .j . -! .1 t nited States...................... Other........................ 3.544 i 3.969 191.519 243.416 618 18.469 `14 162 4.618 44. M2 68.090 679.723 35. $00 316,468 1.996.915 455 540 579 2.060 68.171 656 58.968 10.075 50, lbs 11.541 44.620 964.429 9.8S5 4.003 4.509 7.933 616 18.489 1.313 162 6.69 112.713 809 .................................j S3.267 4.029.191 | 74.978 1.100,303 15S.245 Value 200.487 253.491 491.975 58.090 679.723 47.341 r.ssr 361.055 R 961.344 IS. =11 5.129.496 1935 Australia................ i Belgium.................... .................. France.................................... Germany.................. Italy......................... Japan........................ Netherlands............. Spain............... Cmied Kingdom................. united States............ Other........................ ZOO! 3.761 i:$;i 599.632 ................... 1 25t.' 142 I 514.407 320 6.200 ! 1.438 28.805 1 ............ ___ ! 110.725 j' 700 1' *""*i4.*776'j 4.5M j 61.059 ; .4, | 100.186 j m 290.569 J ........3*594*1* 75.516 i 16.714 | 92.S10 1.440.995 ' 330 | 4.782 1 5.300.176 ; 100.025 J 1.5S5.451 . As given in Tbe Trade of Canada. Ottawa. zoo) 5.M7 i 4.101 i 6.351 I 806 ( 15.597 1 2.371 710 ; 8.176 | 153.869 577 \ 599.632 285.013 260.342 466.867 74.435 028.597 125.501 37.32$ 366,085 4.520.361 21.496 200.211 ' 6,685.657 ijaroibTS INTO THE TOTTED STATES The following table, compiled from Bureau of Mines statistics, shows imports of asbestos into the United States for 6 years. It includes only the crude and mill fibers that constitute, on the basis of value, the principal international trade in_ asbestos. Figures for earlier years may be. found in the Minerals Yearbook and in Mineral .Resources of the"United States, published by the Bureau of Mines. Imports of asbestos into the Coifed Slates. 1930-35 <crude and mill fiber only) Africa.............................. Canada.................... Germany...................... Italy..................... Sonet Russia.................. United Kingdom_____ Belgium......................... J 1930 Short tons Value ......... ............. .......... _____ .......... 3.210 5730,274 3.65S. 195 35A1 83.897 46 8.25^ 660.559 113.664 1931 | 1932 Short tons Value Short tons Value 1.337 8(89.349 47,340 2.123.746 110 10.700 19 9.855 2.186 104.271 953 1.326 31,064 85 INTERNATIONAL TR/ Imports of asbestos into the United State Country of shipment 1333 I f Short 1 , tom s '> Canada........................................... ............ Germany........................................................ Italy............................................................ Sonet Russia.................................................. Cnited Kingdom........................................... Morocco........................................................... 2.324 $234,557 170 , 17.339 1 i 587 Countries of shipment as given in tli necessarily the countries of origin. Ashes was chiefly of Russian origin, and fiber Kingdom, Belgium, and Morocco origins The following table shows imports, bt rears. For Africa and Russia the figu because the origin of fiber shipped from i not be traced exactly. Also, for both th: ing. relative to short fibers, shipments o usual sources have been disregarded. Sources of asbestos imported into tin Cnited fiber .mill I Source 1930 Short tons i Vasiur Short Soviet Russia............................. 3,020 i>l3.y.v% 70.957 3.650.195 4,924 744.456 4t> b. 79. My 4 Source Canada........................ Sonet Russia............. Italy............................. Tom................. ; j4Jmri tun> V.i*ur Shor 2.3Z' til.'. 114 l>2 ! 17 ' !'.?> -.yjy 51.440 ; :.** The following table shows tin- peree value of imports of crudes and mill fibei source during recent years. asarco alv 0006302 SBESTOS >* from Canada, 193$-151 Jer. r' '-n .Mineral Scm'co Division} 19. Sand and waste 1 | I Total ---- tlue Short tons Value Short tons Value 19. $59 M.519 tf.416 11.183: '3.090 1 '3.800 7.387 $.168 $.915 $.326 4.191 i 1 455 540 2.497 58.908 10.075 5a 787 579 2.080 *>8.171 74.178 11. Ml 44.620 964.429 9.685 1.100.305 4,003 4,509 7.933 1.313 6.698 112.713 $09 13S. 215 200.487 253.491 491.975 58.090 679.723 47.841 7.887 361.088 2,961.344 18.211 5.129, SOS 1035 -.*32 l_ \06 ; *. 143; .(*2 mL ::o 1438 $14,407 j 6.200 28.605 i .725, *`23 L ..7j9 1 ,7U I 176 , 700 j 14. 776 j Z?/hT ** *75*516*1 92. '10 1 1.440.995 1 i 4.7S2 j 100. 925 ; 1. TSA ISI 2.004 ! 3. *17 4.101 6.351 $06 15.597 2.371 710 S. 17* 153. 469 1 577 | $99,632 235.013 260.342 466.567 74.435 628.597 125.501 37.328 366.085 4.320.361 21.496 200.211 : 6. SS5.637 32 mmXD STATES frt `Bureau of Mines statistics, lie .,ted States for 6 years. It ibers that constitute, on the basis of 1 trade in asbestos. Figures for Minerals Yearbook and in Mineral iblislied by the Bureau of Mines. ton. 1930-35 (crude and mill fiber only) 1 Short Value *>ns j Short [ Value Value I :oos l $730,274 3.636.195 $3,897 8.752 660.559 113.664 1.337 $189,349 47.340 1123.746 110 19 1168 9.53 9.855 104.271 166.465 1.326 31,064 $5 SI 17.774 1.285.799 30 9.627 ......... 399 INTERNATIONAL TRADE Imports of asbestos into the United States, 1930-35--Continued 55 Country of shipment 1933 Short tons Value 1934 Short tons Value 1935 Short tons Value Canada................................... . Germany......................................................... Sonet Russia.................................................. Voiced Kingdom............................................ 1324 S234.557 48.916 1337.946 6 669 17 8.929 176 17,339 1 587 1.794 3196.479 43.053 1026,161 16 9.775 657 26.434 22 5,016 1128 3294,23L 61032 3.015.247 22 4,632 202 22 11.464 213,698 23,451 1131 Countries of shipment as given in the preceding table are not necessarily the countries of origin. Asbestos shipped from Germany was chiefly of Russian origin, and fiber shipped from the United Kingdom, Belgium, and Morocco originated chiefly in Africa. The following table shows imports, by countries of origin, for 6 vears. For Africa and Russia the figures are approximate only, because the origin of fiber shipped from" nonproducing countries can not be traced exactly. Also, for both this table and the one follow ing, relative to short fibers, shipments of small quantities from un usual sources have been disregarded. Sources of asbestos imported into the United States, 1930--15 (crude and mill fiber only) 1930 1331 ' 1933 source ............... | Short tons | i! Value Short tons j * Value ^ Short tons Value .Uriel.......................................... ! Canada......................................... Sonet Russia.............................. Italy............................................ Total................................ j .0.95 4.924 ^ 79.549 $843.958 3.656.195 744.456 3.752 5.253.361 1290 47.340 1298 19 $355,814 1 1123.746 i 114.971 1 9.855 51.$47 j 2.604.386 | 1.327 31.064 l 85 32,477 | $118,173 1.285.799 30 9.627 1.413.620 1933 1934 1935 . Short tons Value Short tons Value Short cons Value Africa............................................ ! Canada......................................... : Sonet Russia....................... Italy.............................................. j Total................................ | i32S .9I6 182 17 51. 0 3235. 144 1337.952 lS.IXtt 3.929 2.600. DM | 1.516 43.053 657 16 $203.495 1026.(61 26. 434 9.775 ,6.542 j 2.265. $06 | i 1352 1 60,032 } 4.632 J 22! 67.03$ i <i\0.9li 3.U15.217 213.693 u.m 3.660. 202 The following table shows the percentages of both quantity and value of imports of crudes and mill fibers obtained from each foreign source during recent years. ASARCO ALV 0006303 56 ASBESTOS Percentage of crude and mill-fiber asbestos obtained from each of the principal foreign sources. 19JO-3S source MM 1931 ' 1933 Quantity Value Quantity j Value Quantity Value Africa.-.................................... Canada........... ........................... _____ Italy................................................. 16.1 69.6 6.2 14. 1 .1 .2 i 91.1 4..4ii 13.T Sl.C 4.4 .3 4.1 95.6 .3 S. 4 91.0 .6 source Quantity Value Quantity Value Quantity Value Canada........................... ..................... Soviet Russia................................ Italy....................................................... 4.5 95.0 .4 .1 9.0 89.9 ." .4 4.0 94.5 1.4 .1 9.0 89.4 1 1.2 * i 3.5 89. .4 6.9 .1 9.0 84.; 6.0 .3 It. mar be observed that imports from Africa are much higher in value than in quantity. This is due to the fact that only the Iiigherpriced crude fibers can be imported profitably from such a distant source. On the other hand, the percentage in* quantity of Canadian fiber exceeds its percentage in value, because the deposits are near consuming centers, permitting the importation of large quantities of the shorter lower-priced milFfibers. As many manufacturers of.asbestos products are interested chiefly in sources'of supply of the higher-grade spinning fibers, an attempt lias been made to estimate the tonnages received in recent years from the principal producing centers. The following table 'shows the approximate tonnages of spinning asbestos received annually from Canada, Africa, and Russia, and the percentage of the total imports each country furnished. Principal sources of spinning asbestos imported into the United States. 19S4-3J Year Canada1 Africa Russia Short tons Percent of total imports Short tons Percent of total imports Short tons Percent of total imports 3924................................................................... 1925................................................................... 3920................................................................... 3928................................................................... 1929................................................................... 3930................................................................... 1931................................................................... 1932................................................................... 1933........................ .......................................... 3934................................................................... 1935................................................................... 12.463 17.843 i;.6Si 14.953 15.165 18.363 8.473 6, no (4(<<.))380 80 79 7S 66 62 64 50 60 77 -- 3.051 4.390 4.747 6.096 6.778 8.778 3.620 2.290 1.327 2.352 20 56 (*) 20 191 1 21 349 1 27 1.782 2$ 2.339 10 31 1.426 5 21 4.924 29 20 23 2.29S <*) (*) 20 4,632 * Figures for Canadian tonnages are approximate. The following text explains methods of determination. J Less than 0.5 percent. Less than 1 ton. < Data sot available. INTERNATIONAL .teat For the purpose of calculation. Canadian Crude No. 1. Crude No. 2, Crude run-of-min mill fiber, which, since 1920, has been h Figures for the production of Canudiai. J lished annually, but import figures were n until 1927. From 1924 to 1927 it is asum ning fiber bore the same relation to total of spinning fiber bore to total production. } cent of the total Canadian production, excl as "sand, gravel, and stone", was imported is assumed that 85 percent of the spinning was shipped to the United States. Since 1927 the tonnages of crude and Canada have been recorded, but spinni: separately. To determine this tonntim. the various grades of mill fibers (spimu. are imported in the ratio of their productn. the mill stock produced is of spinning gr percent of the mill stock imported is spirin spinning fiber thus calculated is then add< crudes to arrive at the total imports of sp Approximately all imports from the o regarded as spinning fiber. Russian impc separated into crudes and mill fiber, the noBnsyprinenfeinrgri.ng to the preceding table, it: ada"supplied about 80 percent of the tonal In 1927, however, this percentage uroppe> only o(k In 1932 the Dominion again fv of imports, but the total quantity from al lowA.frica supplied about 20 percen: of > during the period 1927-29. when tb pi . higher. Since 1926, imports from I .s 1930 Russia supplied more than oiie-j.ou the United States. Practical cessation 1932 may be attributed to the embargo pi vestigation conducted by the United Sta though the embargo was lifted, imports 1935 they were again almost as large as i Unfortunately, comparison wiri; Cane years subsequent to 1932. because since t for mill fiber are not broken down by cl; bolding its position because African im one-third of the 1927-29 average. The following table shows sources < States of the shorter grades of asbestos c Until recently Canada supplied nearly 1< but since 1932 Cyprus, Soviet Russia, have furnished 4 to 5 percent of the tota 4 ASARCO ALV 0006304 STOS tos obtained from each of the principal tcs, 1930-35 Jim | Quantity 1 Value Quantity Value 16.1 1 14.1 ! } 14 91.1 4-4 .i 13.7 SL 6 4.4 .3 4.1 95.6 .3 5.4 91.0 .6 * 1934 1915 1 1 iue Quantity Value Quantity Value 9.0 *9.9 .4 4.0 94.5 1.4 .1 9.0 1 69.4 f 1.3 1 .4 1 1 3.5 59.5 6.9 .1 9.0 54.7 6.0 .3 from Africa are much higher in to the fact that only the higher1 profitably from such a distant centage in quantity of Canadian e, because the deposits are near nportation of large quantities of jS products are interested chiefly ;rade spinning fibers, an attempt jes received in recent years from The following table 'shows the asbestos received annually front percentage of the total imports `ortea .nto the United States, 1924-35 Africa Russit itcent ftotal uports 50 79 <3 66 62 50 60 --...... Short tons Percent of total imports 1 3. y.i 20 i 4. ,'.V0 20 i 4.747 21 6. 0.774 23 1 e....4 31 s 3. JO 21 2.2V0 20 1 i. JJ7 2. 13 __ __23 ; 2. ?:t 2.552 ................. ! Percent Short tons ) of total imports i 56 i rn 191 349 i 1.782 .? 2.339 1.426 4. *21 2.298 (:) 1S2 20 <') 657 4.632 -5.......... .'Ollowict kxi cxpiiias methods of determination. INTERNATIONAL TRADE 01 For the purpose of calculation, Canadian spinning fiber includes Crude No. 1, Crude No. 2, Crude run-of-mine, and the highest-grade mill- fiber, which, since 1920, has been designated "spinning fiber." Figures for the production of Canadian asbestos by grades are pub lished annually, but import figures were not segregated by trades until 1927. From 1924 to 1927 it is assumed that imports of" spin ning fiber bore the same relation to total imports that production of spinning fiber bore to total production. In other words, if S5 per cent of the total Canadian, production, exclusive of material classed as "sand, gravel, and stone", was imported into the United States, it is assumed that 85 percent of the spinning fiber produced in Canada was shipped to the United States. Since 1927 the tonnages of crude and mill fiber imported from Canada have been recorded, but spinning fiber still is not reported separately. To determine tins tonnage, therefore, it is assumed that the various grades of mill fibers (spinning, shingle, and paper stock) are imported in the ratio of their production; that is, if 25 percent of the mill stock produced is of spinning grade, it is assumed that 25 percent of the mill stock imported is spinning fiber. The quantity of spinning fiber thus calculated is then added to imports of Canadian crudes to arrive at the total imports of spinning stock from Canada. Approximately all imports from the other foreign countries are regarded as spinning fiber. Russian imports in 1931, however, were separated into crudes and mill fiber, the latter being regarded as noBnsyprinenfeinrgri.ng to the preceding table, it may be observed that Can ada supplied about 80 percent of the total imports from 1924 to 1926. In 1927. however, this percentage dropped to 66. and in 1930 it was only 50. In 1932 the Dominion again furnished over three-fourths of imports, but the total quantity from all sources was exceptionally low. Africa supplied about 20 percent of the total each year, except during the period 1927-29, when the proportion was considerably higher. Since 1926, imports from Russia have been considerable: in 1930 Russia supplied more than one-fourth of the requirements of (he United States. Practical cessation of imports from Russia in 1932 mav be attributed to the embargo placed on them during an in vestigation conducted by the United States Tariff Commission. Al though the embargo wa's lifted, imports in 1933 were small, but by 1935 they were again almost as large as in the peak year 1930. Unfortunately, comparison with Canada cannot be made for the years subsequent to 1932. because since that year Canadian statistics for mill fiber are. not broken down by classes. Apparently Canada is holding its position because African imports in 1935 were less than one-third of the 1927-29 average. The following table shows "sources of imports into the United States of the shorter grades of asbestos classed as "stucco and refuse." Until recently Canada supplied nearly 100 percent of the short fibers, but since 1932 Cyprus, Soviet Russia, Finland, and Italy together have furnished 4 to 5 percent of the total. ASARCO ALV 0006305 5S ASBESTOS Imports into the United State* of asbestos classed as "stucco and refuse" c'*uree 1930 Short tons Value 1731 1932 Short tons Value i Short ! tons Value Canada......... IStaovlyie..t..K..u..s.sia.................................................... 12*. ir ' JI. Sli). M A/rica.......................................... :........ 17 1 'iiVj' I2y. 130 ; i.sii. uij S1707 J1.10S.S36 I6IS AJ3 63.606 5827.741 27 ! 316 .......629* ........ 7*719 43 1. !<K 91.113 1 1.111.671 I 64.278 836.571 Smitcc Canada... ! Soviet Russia......... ` '***\! Cyprus.................... Italy........... .......... .............................. i . Finiand........* ...................... i Africa........... ......................--j 1533 Short 1 tons Value 1 1934 : i Short tons i ,* \alue ' 3935 i i | Short tuns tii Jl Value G3.999 631 2,274 9s35 l1 6-4.091 ( / 40.503 37,3M J1 7.764 ] 1.4<M 339 f 912.032 70.007 1.936 2.463 216 3S 100 71,792 I 31.0001402 I 63.005 j 43.611 1.771 ( ' 1.020 | 1.417 ,. 1.112.120 | W.204 181 4,628 523 11 99.547 j 31,470. sas 831 87.841 5.202 416 l.ses. 191 jritim THE UNITED STATES Terr little unmanufactured asbestos is exported from the United States. Recent exports, shown in the following table, have con sisted principally of shingle stock of foreign origin blended in the United States and shipped mainly to Japan, Mexico, and Europe. The exceptionally high value of exports in i92S is due to a large shipment of Russian asbestos to Germany. Statistics of the Depart ment of Commerce also show shipments of about 1.000 tons of foreign crude and unmanufactured asbestos annually under "ex ports of foreign merchandise." These represent transshipments of Canadian material via American ports. Asbestos (unmanufactured) charted front the United States. 192^0 yw Short tons JValue |! I! S1h4,o05rt a,ue {,' Vear ;: cio. n', i1 Value 1924........... j 1270 JJg................1 U09 1927................ j M2$..............| i 3oj> 393.363 | t 1929............. 70.846 J 1930......... 85.922 : i93i......... 4S. 741 j 1632........... 316.632 1933......... 7U9 771 1.714 1.707 1.378 3108.4G7 I S.............j 95.318 122.391 91.936 | j ............. ............. 88,521 't 1.6 , f 3,,-H SW. 182 .67.H96 310,197 Although little unmanufactured asbestos is exported, foreign trade in asbestos products is extensive. The following table shows exports by kinds in 1934 and 1935. Brake linings and textile yarns and packings are the largest items. * MINING METHOD' Manufactured asbestos products exported from Kinds " Product Qu Brake lininc: Molded and Femuoolded......................... Not molded....................................... ....iinearieetl! Paper, millboard, and rollboard.................. ....short toss.. Pipe coverme and cement............................. Textiles, yarn, and packing........................... ................ Q0___ Asbestos rooftop.............................................. Other manufactures....................................... 1. * Quantity noi recorded. PROSPECTING AND EX] Asbestos is usually associated with s recognized by its green or yellowish gr< therefore, the formations in which asbe Asbestos is so resistant to weathering tha knolls or ridges above the level of the su posure may be widened by stripping or i the fiber judged by visual inspection^ Si by weathering, but such effects usually few inches only. Exploration at depth mond- or shot-core drills. Deposits are of test pits which are enlarged into actr able results are obtained. Estimation asbestos-bearing rock is difficult, and s cured only by making actual mill runs. MINING. MET! Asbestos deposits in the various. .a and methods of mining depend greatly In some'places the rock is blasted in o power shovels in much the same way- quarried for the production of crush elaborate systems of underground n General methods followed in the pr brieflv. ARIZONA In Arizona the asbestos occurs in veil diabase intrusions. The reins pinch ai erratic in size and direction that deve definitely as in the mining of mammined in drifts and tunnels, and condii two or more veins of workable size an one tunnel. The soft, flexible fiber harsher, more brittle asbestos may be at variety. i ASARCO ALV 0006306 BESTOS asbestos classed at"ttucco and refute". tJO-iJJ "T" 1931 Value ) shnrt j tons Value 1932 Short tons Value .MQ.583 M ir,o all. in 52.737 5L103.936 2.619 35, 423 315 54.413 | I.IM.H74 | lilt 63,609 629 43 64,278 5R27,744 7.719 1.108 B36.J71 1935 Value Short tons Value Short tons Value $54,647 40.503 37,395 7,764 J. 404 339 *42.052 ; 70.007 2.938 2.463 216 38 100 51.00a 402 63.005 43.611 1.774 1.920 1.417 71. .*52 ; 1.112.129 | 94.204 181 1.623 523 11 51.470.865 834 37,844 5,202 446 M. M7 j 1.565. 191 HE UNTIED STATES estos is exported from the United in the following table, have conc of foreign origin blended in the v to Japan, Mexico, and Europe, exports in i92S is due to a large ermany. Statistics of the Departhipmeuts of about 1,000 tons of -ed -stos annually under "exriiejK. .^present transshipments of torts.. :d from the United States, 192.)--16 rrt ns Value j Year 7119 i .{I j :S| $105. 407 ' 1 1934............. 95.516 , 1935............. 122.291 : 1936............ 94.936 1 38.221 Short t0Q4 1.669 $50 3.744 Value $94.182 3:. *96 310,197 asbestos is exported, foreign trade The following table shows-exports te linings and textile yarns and MINING METHODS 59 Manufactured asbestos products exported from the United States 19Si-3S, by kinds Product 1934 1935 Quantity Value Quantity Value Brake linine: Not molded............................................. Paper, millboard, and rollboard........................ Textiles, yam. and packing................................ ........... do.... Asbestos roofing.................................................... Other manufactures......................................... .short tons.. (*) 1.641.333 602 1..369 619 26.457 *799 5607.193 255.018 96.154 *129.190 *594.625 241.410 75.254 146,670 O) 1.429.520 767 1,233 715 31. IU 921 5651,338 231,381 130,573 662.321 106.678 190.206 Quantity not recorded. t Revised fleure. PROSPECTING AND EXPLORATION Asbestos is usually associated with serpentine, a mineral easily recognized by its green or yellowish green color and greasy luster; therefore, the formations in which asbestos occur are trace'd easily. Asbestos is so resistant to weathering that outcrops frequently occupy knolls or ridges above the level of the surrounding country. ' The ex posure may be widened by stripping or trenching, and the quality of the fiber judged by visual inspection. Surface fiber may be discolored by weathering, but such effects usually are confined to a depth of a few inches only. Exploration at depth may be conducted with dia mond- or shot-core drills. Deposits are commonly explored by means of test pits which are enlarged into active quarries or mines if favor able results are obtained. Estimation of the fiber content of an asbestos-bearing rock is difficult, and satisfactory results can be se cured only by making actual mill runs. MINING METHODS' Asbestos deposits in the various localities differ widely in character, and methods of mining depend greatly on conditions of occurrence. In some places the rock.is blasted in open quarries and loaded with power shovels in much the same way as limestone or trap rock is quarried for the production of crushed, stone. In other deposits elaborate systems of underground mining have been developed. General methods followed in the principal districts are outlined brieflv. ARIZONA In Arizona the asbestos occurs in veins in the Mescal limestone near diabase intrusions. The veins pinch and swell irregularly and are so erratic in size and direction that development cannot be planned as definitely as in the mining of manv other minerals. The fiber is mined in drifts and tunnels, and conditions are most favorable where two or more veins of workable size are close enough to be worked in one tunnel. The soft, flexible fiber is most desired, but veins of harsher, more brittle asbestos may be associated closely with the softer variety. ASARCO ALV 0006307 60 ASBESTOS Modified room-and-pillar mining methods are followed. Much of the waste rock in each room is built up in dry walls about every " 10 feet for roof support. Excess waste and fiber-bearing rock are wheeled to chutes. Cobbing and sorting are done in the stopes on a contract basis. Two grades of fiber are usually produced, and con tractors are paid 2 cents a pound more for the long than for the short fiber recovered. Mexican labor is found to be most satisfactory. Several thousand feet of tunnels have been driven on Ash Creek and at other points in the southern part of the State. Production costs at the best mines are said to be about 40 cents per pound of fiber produced. From 25 to 60 pounds of asbestos are recovered for each running foot of a i1/^ by 7-foot tunnel. VERMONT The chrysotile-asbestos quarries of Vermont are situated at an elevation of 2.500 feet on the south side of Belvidere Mountain ap proximately 15 miles from Hyde Park, the nearest railway station. As the rock outcrops at this point, very little stripping is necessary. "Whatever overburden is encountered is removed in stoneboats drawn by horses because of the steep slope of the mountainside. The quarry face is about 150 feet high, and individual benches are 12 to 15 feet high. Blast holes are sunk with hammer drills. Two electric power shovels with Hi-cubic yard dippers are used for loading into 3 motor trucks with 10-ton steel rear-dump bodies. The trucks dump the rock into a chute, which feeds a 28- by 36-inch jaw crusher. GEORGIA AND MARYLAND Mass-fiber anthophyllite, the varietv found in Georgia, usually occurs in pockets or lenses confined, for the most part, to surface zones: therefore it is quarried in shallow open pits. As operations are small, the material is loaded by hand into small cars that convey it to the mill or to the transshipping point. Quarries at Sail Moun tain and Hollywood, Ga., are of this type. Slip-fiber anthophyllite, on the other hand, occurs in narrow shear zones, which necessitate excavation in narrow opencuts or underground workings. The Pvlesville (Md.) operations are examples. CANADA Stripping is a serious problem in the Quebec district, as over burden ranges from 6 to 8 feet to a maximum of 125 feet' in depth. For many years, asbestos was obtained from large open-pit quarries served bv overhead cableways. About 1927, methods were modified by the introduction of new equipment--cranes or power shovels were introduced for loading, locomotives were used for hauling cars on the quarry floor, and cable hoists removed the cars from the pits up inclined planes or through tunnels. Power-shovel loading, crushing, and subsequent recovery of crude fiber from picking belts are gradu ally replacing hand coobing of crudes in the quarry. This method reduces costs but also tends to reduce recovery of crude. The prin cipal reasons for the change were (1) decreasing markets for crudes Bureau nf Mines FlCURET.--Sied cbuiesand cbaiu-cbuu gules, A*r*sios Cot ASARCO ALV 0006308 ASBESTOS Sning methods are followed. Much of is ' up in dry walls about every rcess__. jSte and fiber-bearing rock are tn'd sorting are done in the stopes on a f fiber are usually produced, and conid more for the long than for the short r is found to be most satisfactory, nnels have been driven on Ash Creek rthem part of the State. Production Id to be about 40 cents per pound of 3 pounds of asbestos are recovered for 7-foot tunnel. 'xs.hokt rries of Vermont are situated at an south side of Belvidere Mountain ap'de Park, the nearest railway station, lint, very little stripping is necessary, itered is removed in stoneboats drawn lope of the mountainside. The quarry .i individual benches are 12 to 15 feet h hammer drills. Two electric power 'Uppers are used for loading into 3 rear-dump bodies. The trucks dump ds a 28- by 36-inch jaw crusher. AOT 'HUJ.TLASrO t variety found in Georgia, usually ifined, for the most part, to surface in shallow open pits. 'As operations 1 by ' -'d into small cars that convey ipir unt. Quarries at Sail Mounf this type. Slip-fiber anthophvllite, arrow shear zones, which necessitate s or underground workings. The examples. ANABA em in the Quebec district, as overto a maximum of 125 feet in depth, btained from large open-pit quarries About 1927, methods were modified iment--.wanes or power shovels were fives were used for hauling cars on s removed the cars from the pits up els. Power-shovel loading, crushing, e fiber from picking belts~are graducrudes in the quarry. This method educe recovery of crude. The prine (1) decreasing markets for crudes ASARCO ALV 0006309 MINING METHODS 61 due to the introduction of molded brake linings: (2) increasing sup plies of crudes from Rhodesia, the Union of South Africa, and Russia; (3) a decreasing proportion of crudes in the rock; and (4) lower prices for crudes. A still later development in the Quebec district is the introduction of shrinkage stoping. The stone is drawn through chutes directly into boxes trammed by hand or electric locomotives through tunnels leading to the open pit, from which the material is hoisted by high speed cableways. The most recent innovation is an elaborate block-caving system at the King Mine of the Asbestos Corporation, Ltd., patterned after the system employed in some of the Arizona copper mines. A haulage level is established 500 feet below the surface. The overlying fiberbearing rock is worked in blocks 160 feet square. Four grizzly drifts 40 feet apart are driven beneath the block 40 feet above the haulage level. The drifts are timbered and are provided at 20-foot intervals with heavy steel-rail grizzlies with 16-inch openings. "Finger raises" are driven upward at each side of the drift, and 20 feet above the drifts the block is undercut completely by driving drifts and blasting out the intervening pillars. The finger raises are funnelecl to permit access to large pieces of rock that must be broken at the grizzlies. The boundaries of the block are weakened by projecting raises and con necting drifts. The entire, block sinks and is broken up by its own weight. Rock is worked through the grizzlies until the'block is exhausted. Satisfactory results have been attained, and mining costs are considerable- lower than by the shrinkage-stoping method. Details of the process have been published." Figure 7 shows loading chutes on the haulage level. The glory-liole method also is used. Raises are driven to the surface from an established level, and the rock is broken down in a funnels shaped opening at the top of the raise. Broken rock is drawn oif into cars and removed througn a tunnel. Most drilling is done" with hammer drills held in the hands, but tripod drills are used for flat breast holes and for steep bench holes. Tripod drill holes range up to 18 feet deep. Heavy equipment is some times employed to sink holes to depths of 40 feet or more. Wet drill ing is impractical because the fiber forms a spongy mass that tends to clog the drill hole. ff the filier-bearing rock is quarried in shallow pits, loaded cars tnav be hauled in trains clirectly from the face. An elaborate spiral trade lay-out is in use at one pit. "Mining costs are variable, depending upon the percentage of fiber in the rock, hardness of rock, quarry conditions, and many"other fac tors. Ross * gives a direct mining and milling cost of $10 to $15 per ton of fiber where the rock is loaded with power shovels, and where recovery is 3 to 12 percent of gross quarry output. Where the rock is hand-sorted, shoveled into boxes, ana elevated with crane or cableway hoists, the direct operating costs may range from $20 to $60 per toil of fiber produced. * Ross. J. O.. Block Caving at the Kins Mine of the Asbestos Corporation. I.rd.. Tlietford Mines. Quebec: Canadian Min. and Met. Bull. 264. April 1934. pp. lS4-2ts. M Ross. J. G., Chrysotlle Asbestos In Canada: Canada Dept, of Mines Bull. TOT. U`3l, p. 5T. 104342*--3T------5 'l\ ASARCO ALV 0006310 62 asbestos __ RHODESIA Twojnining methods--quarrying and shrinkage stoping--are used at the Shahani. the largest asbestos mine in Rhodesia. The quarrying method is peculiar in that the rock is broken in open pits but removed through vertical shafts. Shafts or winzes are sunk in row? 50 to 60 feet apart and connected with crosscuts at a lower level. The rock arouna them is drilled and blasted, and the fiber is cobbed from the broken fragments. In order that the fiber may be broken as little as possible, light powder charges are fired in shallow holes. The broken rock is thrown into the shafts, which are kept nearly full, drawn into cars on the level below, and taken to the mill for extraction of the short fiber or recover}' of the long fiber not re moved in cobbing. The cobbed fiber is thrown down a separate shaft. The shafts are also employed for disposal of waste and for drainage. The shrinkage-stoping'method was introduced about 1926. The ground is removed in blocks 80 feet square, leaving pillars 20 to 30 feet wide, which are subsequently reclaimed. UNION OF SOUTH AFRICA The largest asbestos mines in the Union of South Africa are those producing chrysotile in the Barberton district of the Transvaal. The asbestos-bearing serpentine occurs in two zones. _ The upper one. known as the "ribbon reef", contains short-fiber veins, and tne lower one provides long fiber. The belt dips 10 to 20. and underground mining is practiced. The ribbon reef is stoped first, and at a later stage the rock carrying long fiber is removed from the footwall. Two large mines have been developed in this territory. The Kew Amianthus mine is worked on several levels. In 1928* it extended down the dip a distance of 1,650 feet from the outcrop. In the same year the Munnik-Myburg mine comprised about 3,300 feet of under ground workings. In the Carolina district of the Transvaal chrvsotile occurs in cross fiber veins occupying a 5-foot zone of altered dolomite dipping 86 to 15s. Mines have'been operated since 1905 and have reached a depth of 300 feet. Amosite of the Lvdenburg district of the Transvaal occurs in banded ironstones that have been highly folded and contorted. The fiber-bearing beds usually stand at angles rangin'! from 15 to vertical. As thev are unsuited for open-pit working, underground mining is generally followed. Where the beds are intersected bv transverse valleys, tunnels are driven along the strike, and the fiber-nearing rock is stoped out at various levels. Outcrops are numerous over a wide area, and fiber is obtained from many mines worked at relatively shallow depths. The largest mines are the Egnep and the Amosa, situated near Penge. In this region the fiber-bearing zone dips from 15 to 22. The Egnep mine is worked on seven levels. A vertical shaft 215 feet deep serves the seventh level and is connected with the sixth bv a crosscut. The Amosa mine, as described by Hall in 1930, comprised 11 drifts, starting from the outcrop and ranging from 80 to 1,140 feet in length down the dip. An inclined shaft 320 feet long corresponds to a vertical depth of 290 feet. mining METEi Crocidolite (blue asbestos), which is s territory north of the Olifants River, is workings. Crocidolite also occur.' a and Ivuruman districts of the Cab jf irregular and discontinuous, ami svste lowed generally. Much of the fiber is c or from shallow mines worked ov nati worked to depths of 250 feet wi;h drif Hall describes in considerable deta Africa.41 RUSSIA The asbestos deposits of the Bajam burden. Hand methods of removal w shovels or hydraulic methods have extent. More than 20 shallow, open quarries Up to 1929 drilling was the oiiiy mec operations being conducted with ham milling facilities, hand pickim: becan process, and only one-fourth to one-1 sent to the mill. The average fiber < only about 6 percent, but because of hand picking, that sent to the mill wa: The first steps toward more comple1929. with the installation of 2- to 4-ti with fixed foot towers and traveling inclined haulageways served by electr in benches 5 to 6 meters high a:.d claswaste. In 1929 two shafts were sunk and at a depth of 50 meters. They were which proved uneconomical. This largely superseded in 1930 by i with transport by locomotives . u cars are taken by electric hoists. Mil 75 cents a metric ton of rock. De methods have been supplied by Ru K CTFRU Chrysotile asbestos, occurs or. the regular veins traversing serpentine The expansion accompanying metan resulted in excessive fracturing, whi workings consist of open-pit terrace250 feet. Much of the rock is so fi can be broken with picks.without tht when compressed-air drills were ii drilled for blasting by hand methods a Hall. A. L., Asbestos In the Union of So Mem. 12. 2d ed,, 1930. ru Keyser. Welter A.. Mining Asbestos in September 1933, pp. 37-3$l. ASARCO ALV 0006311 :stos 3ESIA g a; hrinkage stoping--are used s mht_in Rhodesia, r ih that the rock is broken in open shafts. Shafts or winzes are sunk mnected with crosscuts at a lower rilled and blasted, and the fiber is s. In order that the fiber mav be owder charges are fired in shallow n into the shafts, which are kept level below, and taken to the mill recovery of the long fiber not re:r is thrown down a separate shaft, lisposal of waste and for drainage, was introduced about 1926. The :et square, leaving pillars 20 to 30 reclaimed. UTH AERICA e Union of South Africa are those ton district of the Transvaal. The s in two zones. The upper one, ns short-fiber veins, and the lower dips 10 s to 20. and underground reef is stoped first, and at a later is removed from the footwall. loped in this territory. The New veral levels. In 1928 it extended ;et from the outcrop. In the same mprised about 3,300 feet of under ran 1 chrvsotile occurs, in cross of a^ered dolomite dipping 8 to ice 1905 and have reached a depth trict of the Transvaal occurs in highly folded and contorted. The angles ranging from 15 to vertical, working, underground mining is >eds are intersected bv transverse .e strike, and the fiber-bearing rock utcrops are numerous over a wide many mines worked at relatively ep and the Amosa. situated near earing zone dips from 15 to 22. n levels. A vertical shaft 215 feet is connected with the sixth by a cribed by Hall in 1930. comprised i and ranging from 80 to 1.140 feet led shaft 320 feet long corresponds MINING METHODS 63 Crocidolite (blue asbestos), which is associated with amosite in the territory north of the Olifants River, is mined in small underground workings. Crocidolite also occurs over a wide area in the Prieska and Kuruman districts of the Cape of Good Hope. The veins are irregular and discontinuous, and systematic mining cannot be fol lowed generally. Much of the fiber is obtained from small open pits or from shallow mines worked by natives. A few mines have been worked to depths of 250 feet with drifts over 1,000 feet long. Hall describes in considerable detail asbestos mining m South Africa.*1 RUSSIA The asbestos deposits of the Bajanova district have a thin over burden. Hand methods of removal were first employed, but power shovels or hydraulic methods have superseded them to quite an extent. More than 20 shallow, open quarries were worked for many years. Up to 1929 drilling was the ordy mechanical process used, all other operations being conducted with hand tools. Owing to inadequate milling facilities, hand picking became an important concentration process, and only one-fourth to one-fifth of the rock quarried was sent to the mill. The average fiber content of the rock mined was only about 6 percent, but because of the concentration attained by hand picking, that sent to the mill was 22 percent. The first steps toward more complete mechanization were taken in 1929, with the installation of 2- to 4-ton capacity overhead cableways with fixed foot towers and traveling head towers, supplemented byinclined haulagewavs served by electric hoists. The rock was blasted in benches 5 to~6 meters high and classified into crudes, mill feed, and waste. In 1929 two shafts were sunk and connected with a haulage level at a depth of 50 meters. They were designed for glory-hole mining, which proved uneconomical. This method was supplemented and largely superseded in 1930 by electric-shovel loading in open pits with transport by locomotives to inclined haulagewavs, up which cars are taken by electric hoists. Mining costs are estimated at about 75 cents a metric ton of rock. Details of quarrying and mining methods have been supplied by Ru Keyser.42 CYPRUS Chrvsotile asbestos occurs on the slopes of Mount Troodos in ir regular veins traversing serpentine formed by alteration of olivine. Tile expansion accompanying metamorphism of the original olivine resulted in excessive fracturing,, which makes excavation easy. The workings consist of open-pit terraces reaching a maximum height or 250 feet. Much of the rock is so fractured and decomposed that it can be broken with picks without the aid of explosives. Before 1927. when compressed-air drills were introduced, the harder rock was drilled for blasting by hand methods. When 40-pound hand hammer Hall. A. L.. Asbestos In the Colon of South Africa: Geol. Survey of South Africa Mem. 12. 2d ed.. 1D30. " Ru Keyser. Walter A.. Mining Asbestos in 0. S. S. R.: Eng. and Min. /our., vof. 134. September 1933, pp. 375-381. ASARCO ALV 0006312 64 ASBESTOS drills are used, 3-inch holes ranging in depth from 8 to 12 feet are sunk at a rate of about 10 feet an hour. The larger masses of barren rock are removed as waste. Fiber-bearinir material is turned over to facilitate drying in the hot sun. and it is then passed over gravity screens. That passing through an 15-mm-mesh screen and retained on a 5-mm screen (nliout. one-fifth of the total material quarried) is sent to the mills for recovery of the fiber. Oversize rock retained on the upper screen, and sand passing the lower screen are trammed to waste heaps. The quarries are worked from March to December. In 1027 approximately 6.000 workers were employed in the quarries and about 1.500.000 rons of rock were broken. Operations were still, more extensive in 1928 and 1929. decreased greatly during the de pression Tears, but recovered substantially in 1934 and 1935. Fur ther details of quarry methods are given by "Whitworth." Production consisted exclusively of short fiber until 1934. when, according to report, a small quantity of spinning fiber was shipped. CHINA Primitive methods are followed in the Laiyuan district. The min ing tools used are hammers, chisels, picks, and shovels. No machin ery or explosives are employed. Small inclined tunnels are sunk along the veins to a maximum depth of about 30 meters. The fiber is cobbed and sorted by hand. Mining costs are said to range from 896 to 8137 a ton of fiber produced. MILLING METHODS CLASSIFICATION OF FIBER A brief discussion of the method of classifying asbestos fibers is a necessary preliminary to a description of milling methods. Canadian and Vermont- asbestos fibers are divided into three main groups--crudes, mill fibers, and shorts. The term "crude" is applied to fiber of spinning grade, measuring three-eighths inch or longer, that,is hand-cobbed' and not passed through a "mill. Mill fibers "are obtained by crushing and beating the fiber-bearing rock until the asbestos is freed, and then removing the fiber from the rock by screening or air separation. Shorts are the lowest grades of mill products. Russian asbestos also is classed as crudes and mill fibers, but the term "crude5* is applied somewhat loosely; it apparently includes some spinning fiber that has been prepared mechanically.* The term "crude" is not generally applied to African products. Spinning fibers comparable in quality with Canadian crudes are prepared by hand-cobbing alone or in conjunction with simple me chanical crushing, disintegrating, and screening processes. A much larger proportion of the African long fibers has been prepared mechanically during recent years. Mill fibers of the shorter grades constitute the largest part of the tonnage. Virtually all of the asbestos produced in Cyprus is classed as mill fiber. - 43Whitworth. 51.. Cyprus and Its Asbestos Industry: Mining Mag. (London), vol. 38, September 192S, pp. 113-150. MILLING METHODS GENERAL FEATURES OF KILLING As pointed out on preceding pages, tl c i ile occurrences are (1) deposits derive, ,/c tite-pyroxenite rocks and (2) denosits d limestone intruded by diabase. The "first typ of asbestos in Vermont, Quebec, the UralM the Transvaal. The second type, which rep of the world output, occurs in Arizona; Min Carolina district of South Africa. The pr associated with asbestos of the first type is terials with the second type are serpentine ai tile also is serpentine, differing only in str it is obvious that the milling of chrvsotile n forms of ore concentration. As the'valuable consist of the same material, neither chcmi cific gravity can be utilized as the basis for s that makes mechanical separation of chrvso structure, which permits it to be opened o separate filaments., thus making it umenabl gangue by air suction and screening. The value of chrvsotile asbestos'depends (he fiber. When fiber three-eighth? inch 1 fiber three-fourths inch long is worth ap Thus, it is apparent that breaking fibers matelv three-fourths of their value. The underlying the milling of asbestos, there: fiber from rock with minimum breakage of spare the fiber unnecessarilv rough xveatn: break the rock effectively. Modern mills a separated fiber after each crushing jiroces soon as it is formed, and to keep hard, ba If. fiber already freed from rock enter" *lu with sand and rock fragments, it wi! t Asbestos milling consists essentially Ol eo: recrushing in stages, each step being folk separation of fiber from rock. Another peculiarity of asbestos millii known method of testing the qualiry of appears to contain little fiber may yield one that appears promisingmayshowadis As both the valuable mineral and the assay is useless. A laboratory-scale cru unit*might give results that differ widely mill operating on the same rock. Altln coverable fiber in a rock cannot be ueterm yield can be calculated from the mill o the value of a fiber-bearing, rock can be a test run in a commercial mill. In the following discussion of millin world, Canadian practice is considered fii the pioneers in the asbestos industry, anc lished a basis for practice in other countr ASARCO ALV 0006313 iTOS ;g in depth from 8 to 12 feet are our 'he larger masses of barren >eai__material is turned over to id it is then passed over gravity 18-mm-mesh screen and retained of the total material quarried) is fiber. Oversize rock retained on the lower screen are trammed to 'irked from March to December, rs were employed in the quarries re broken. Operations were still. lecreased greatly during the deintiallv in 193-1* and 1935. Furriven by Whitworth.4* of short fiber until 1931, when, y of spinning fiber was shipped. i : the Laiynan district. The minpicks. a nd shovels. Xo machin~hnall inclined tunnels are sunk h of about 30 meters. The fiber .ing costs are said to range from HETHODS 7 0E S13ES of classifying asbestos fibers is a on of milling methods, bers are divided into three main ts. term "crude" is applied ng t.,,ce-eighths inch or longer, through a mill. Mill fibers are *he fiber-bearing rock until the ng the fiber from the rock by s'are the lowest grades of mill : crudes and mill fibers, but the loosely: it apparently includes repared mechanically, v applied to African products, lity with Canadian crudes are in* conjunction with simple meid screening processes. A much long fibers has been prepared Mill'fibers of the shorter grades nage. duced in Cyprus is classed as ndustrr: Mining Mac. (London), rol. 39. MILLING METHODS 65 GENEBAL FEATTTBES OF OTLLDTG METHODS As pointed out on preceding pages, the two major types of chrysofile occurrences are (1) deposits derived from alteration of pendotite-pyroxenite rocks and (2) deposits derived from dolomitic limestone intruded by diabase. The first type is the principal source of asbestos in Vermont. Quebec, the Ural Mountains, Rhodesia, and the Transvaal. The second type, which represents a. small fraction of the world output, occurs in* Arizona; Minusinsk, Siberia; and the Carolina district of South Africa. The principal gangue material associated with asbestos of the first type is serpentine, and the ma terials with the second type are serpentine and limestone. As chryso- tile also is serpentine, differing only in structure from the gangue, it is obvious that the milling ot chrysotile must differ from ail other forms of ore concentration. As the valuable mineral and the gangue consist of the same material, neither chemical composition nor spe cific gravity can be utilized as the basis for separation. The property that makes*mechanical separation of chrysotile possible is its fibrous structure, which permits it to be. opened or divided by impact into separate filaments, thus making it amenable to separation from the gangue by air suction and screening. The value of chrysotile asbestos depends largely on the length of (he fiber. When fiber three-eighths inch long'is worth $100 a ton, fiber three-fourths inch long is worth approximately $400 a ton. Thus, it is apparent tliac breaking fibers in half destroys approxi mately three-fourths or their value. The most important principle underlying the milling of asbestos, therefore, is the separation of fiber from'rock with nnnimuni breakage of fibers. The best machines spare the fiber unnecessarily rough treatment and at the same time break the rock effectively. ^Modern mills are designed to remove the separated liber after each crushing process, to separate the sand as s-oon as it is formed, and tp keep hard, barren rock out of the mill. If fiber already freed from rock enters the next.crushing unit along with sand and rock fragments, jfc will be broken into shorter grades, i Asbestos milling consists essentially of coarse crushing, drying, and recrushing in stages, each step being followed by screening and air separation of fiber from rock. .* ' Another peculiarity of asbestos milling is the absence of any known method of testing the quality of'mill feed. A rock that appears to contain little fiber may yield a fair return: conversely, one that appears promisingmayshbwadisappointingly low recovery. As both the valuable mineral and the gangue are serpentine, an i assay is useless. A laboratory-scale crushing and fiber-separating l unit might give results that differ widely from those of a commercial mill operating on the same rock. Although the percentage of re coverable fiber in a rock cannot be determined in advance, the actual j yield can be calculated from the mill output. A fair estimate of the value of a fiber:bearing rock can be obtained only by making a test run in a commercial mill. In the following discussion of milling methods throughout the | world, Canadian practice is considered first because Canadians were J the pioneers in the asbestos industry, and their methods have estab- l lished a basis for practice in other countries. J ASARCO ALV 0006314 06 ASBESTOS CANADA PiiElVlEATIOX Or CRVDZS In Canada the associated rock is broken free of the largcr-fiber reins by sledging. and the masses of fiber are sorted by hand. The fiber with some adherin': rock is dried on steam coils and then taken to the- cobbing sheds, where the fiber veins are flattened with a hand hammer, freeing them from adhering rock. The separated rock, dust, and short fibers are dropped into a receptacle under the bench, and the remaining hi<rh-grade fibers are classed as Crude No. _ 1. material three-fourths Inch long and over, and Crude No. 2. material three-eighths to three-fourths inch long. To separate further the short fiber and rock dust. Crude No. 1 is screened on a flat shaking screen with three-eighths-inch holes and No. 2 on one with threesixteenths-inch holes. After being screened, the fibers are bagged in jute bags of 100 pounds capacity. _ Five to twentv percent of rock fragments, dust, and short fiber still remain in the crudes as sold, ancT these impurities are separated at the factory where asbestos products are manufactured. Rejects accumulated in preparing crudes are utilized as mill fibers or sold as screenings. Crudes con stitute a small proportion of the recoverable fiber but are the most valuable products. Ru Keyserlias developed a process of preparing long fiber me chanically, by which rolls are used instead of hand hammers. The fibers are graded on screens that are so operated that the fibers are held in a horizontal plane. The claim is made that fibers thus pre pared are superior in grade and purity to hand-cobbed crudes. MILLING PRACTICE Mechanical means of preparing fiber began in Quebec in 1838, and by 1S96 important tonnages of niilled fiber were sold. The principal processes involved in milling are crushing, drying, storing, fiberizing, screening, air separating, and grading. PEEZIltINAET CBCSHIXO . Rock from the quarries or mines is dumped into a so-called "sluice" that holds several carloads. The sluice may have a railroad-railgrizzly bottom that provides a bypass for fines. The primarycrusher feed from the sluice is controlled by finger gates--that is, suspended rails that may be moved up or down. A jaw crusher with a 36-inch by 24-inch opening set for a 4- to 6-inch discharge is the most popular primary breaker. Larger or smaller units may be employed as needed.' Crushers discharge to picking belts, where liberated crudes are removed by hand. DETTJTG Tlie quarry rock contains considerable moisture, in winter even snow and ice, and it must be dried for proper milling. Standard rotary driers generally are used. The shells are 40 to 60 feet long, 4 to 6 feet in diameter, and inclined at an angle of 7. The material is lifted by a series of blades and allowed to fall through the cur- Ru Keyser. Walter A.. Mechanical Cobbing of Chrrsotile Asbestos: Eng. and Min. Jour,, voL 134. no. G. June 1933, pp. 235-237. Milling M'EfSd rent of hot air that circulates through range from 30 to 60 tons of rock an Tio cents a ton. Stack driers also are used and art ,d cal. Rock is elevated to the top of a 50-f and allowed to fall through a rising cur interrupt the speed of the descent. STORAGE A large supply of rock in storage insm is fed to the mill on belt conveyors can neath the storage bins. By drawing roc same time material of comparatively uni is obtained. Bins having capacities of 2 use. HBEKIZING Although crushing, drying, and stori form throughout the Canadian distri greatly. No flow sheet can be applied must he modified to suit the rock. A mi would be too severe for fiber enclosed in : ing may be done with jaw or gyratory c or hammer mills. A straight 'impact tl is preferred to a grinding or shearing less desirable tlianlmpact mills. The following flow sheet, given by the best modern practice. Grizzly in rock sluice. Jaw crusher. Drier. Grizzly, fines to screens fitte Gyratory crusher. Screens with suction. Rolls. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Rotary graders aud llat clea Floats bin. Sand to dump. It will be observed that the principleeach stage of crushing is followed strict According to this now sheet, erushin is accomplished with gyratory crushers Jumbo, which is manufactured locally, feet long and 24 to 30 inches in diani. horizontal shaft consist of arms that sl mers. The beaters are set at intervals 45 Ross, J. G., CbrysotUe Asbestos In Canada: Ca p. 42. I ASARCO ALV 0006315 -SBESTOS Canada sror csudes >ck isTjroken free of the larger-fiher -ses of liber are sorted by hand. The is dried on steam coils and then taken i fiber veins are flattened with a hand adhering rock. The separated rock, >ed into a receptacle under the bench, * fibers are classed as Crude No. _ 1, s and over, and Crude No. 2, material Inch long. To separate further the le No. 1 is screened on a flat shaking holes and No. 2 on one with threeing screened, the fibers are bagged in ity. _ Five to twenty percent of rock r still remain in tne crudes as sold, rated at the factory where asbestos Rejects accumulated in preparing s or sold as screenings. Crudes conle recoverable fiber but are the most process of preparing long fiber me.sed instead of hand'"hammers. Tha it are so operated that the fibers are e claim is made that fibers thus pre>1 purity to hand-cobbed crudes. -G PRACTICE s fiber began in Quebec in 18S8. and Tilled fiber were sold. The principal crup^-^g, drying, storing, nberizing, adh ARY CEUSHISO es is dumped into a so-called "sluice-1 he sluice may have a railroad-raili bypass for fines. The primarvcohtrolled by finger gates--that is, ed up or down. A jaw crusher with for a 4- to 6-inch discharge is the Larger or smaller units may be discharge to picking belts, where hand. 1YIXG siderable moisture, in winter even .-ied for proper milling. Standard The shells are 40 to 60 feet long, ed at an angle of 7. The material d allowed to fall through the cur Ming of Chiysotlle Asbestos: Eng. and Min. Milling methods 67 rent of hot air that circulates through the cylinder. Capacities range from 30 to 60 tons of rock an hour and costs from 4 to 18 cents a ton. Stack driers also are used and are said to be much more economi cal. Rock is elevated to the top of a 50-foot stack 7 feet in diameter and allowed to fall through a rising current of hot air. Grid bars interrupt the speed of the descent. STORAGE A large supply of rock in storage insures regular mill feed. Rock is fed to the mill on belt conveyors carried in concrete tunnels be neath the storage bins. By drawing rock from several gates at the same time material of comparatively uniform size and fiber content is obtained. Bins having capacities of 25,000 to 150,000 tons are in use. FTBERIZKJO Although crushing, drying, and storing methods are fairly uni form throughout the Canadian district, milling methods vary greatly. No flow sheet can be applied generally because milling must fie modified to suit the rock. A method suitable for hard rock would be too severe for fiber enclosed in soft rock. Secondary crush ing may be done with jaw or gyratory crushers, rolls, Symons cones, or~hanimer mills. A straight impact that, frees and fluffs the liber is preferred to a grinding'or shearing action. Therefore, rolls are less desirable thanlmpact mills. The following flow sheet, given by Ross,*5 probably represents the best modern "practice. Grizzly in rock sluice. Jaw crusher. Drier. Grizzly, fines to screens fitted with suction. Gyratory crusher. Screens with suction. Rolls. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Jumbo. Screens with suction. Rotary graders and flat cleaning screens. Floats bin. Sand to dump. It will be observed that the principle of removing the fiber after each stage of crushing is followed strictly. According to this flow sheet, crushing beyond the primary stajre is accomplished with gyratory crushers and Jumbo machines. The Jumbo, which is manufactured locally, is a horizontal drum 6 to 8 feet long and 24 to 30 inches, in diameter. Beaters attached to a horizontal shaft consist of arms that support manganese-steel ham mers. The beaters are set at intervals of 6 or 8 inches along the "Ross, J. G., Chrysolite Asbestos In Canada: Canada Dept, of Mines Bull. TOT. 1931. p. . ASARCO ALV 0006316 6S ASBESTOS shaft and clear the inside of the shell by about 14 to 1 inch. They are turned at an angle to direct the broken rock toward the discharge end. Tlie shaft rotates at 400 to 800 revolutions per minute, according to the nature of the rock treated. Insread of the Jumbo machine.'some mills employ various types of cyclones, which beat rhe rock to a powder. The Laurie cyclone consists of a cast-iron chamber in which two beaters shaped like ship propellers are driven in opposite directions at a speed of 1.700 to 2.000 revolutions, per minute. In the Pharo cyclone the beaters revolve in the same direc tion and the rate of discharge is controlled by gates. The Torrey cyclone is somewhat like the Jumbo, except that the axis of the heater arms is vertical. SCREENING Shaking screens actuated by eccentrics generally are used, although vibrating screens of the Hum-mer type also are employed. Usual sizes are 3 to 5 feet wide and 8 to 12 feet long. Perforated steel plates are more generally xtsed than wire mesh. Screens with holes up to three-eighths of an inch and larger are used for scalping, and smaller openings down to one thirtv-second of an inch for the very fine materials. "Wire screens ranging from 3 to 24 meshes to the inch are commonly used for cleaning fiber. Fines pass through the openings, but the coarser rock .fragments and longer fibers remain on the screen. The shaking action brings the fiber to the surface of the bedded-rock fragments, and it is removed by air-suction equipment that will be described later. Thus, each screen furnishes three products--fines that pass through as waste, coarse rock fragments discharged at the end. and fiber col lected by suction. Oversize rock fragments pass to the next fiberizing unit. AIR SUCTION Filler segregated on the surface of a layer of rock fragments on the screen'is removed through suction'hoods that operate on the principle of a vacuum cleaner. The opening of the suction hood is ' 3 to 4 inches wide and extends across the full width of the screen at its lower end. The cross-section area of the narrow opening is the same as that of the pipe into which it converges, which ranges from 12 to 20 inches in diameter. Large fans produce the necessary vac uum. A 10- to 15-liorsepower motor is required to drive a fan giving the necessary lifting power through a pipe 15 inches in diameter. The air current sweeps the fiber from the screens, carries it through pipes, and aspirates it in collecting chambers, where the diminished rate of the air current permits it to fall. The dust-laden air from the fans is blown into dust chambers, and the fine materials that settle there are returned to the mill, where the longer fibers are separated and the extremely short grades are bagged and sold as `floats." WET PROCESS Considerable progress has been made in developing a wet process for treating Canadfan asbestos. Some claim that wet treatment inwolves less breakage of fiber and a higher recovery. Experiments were begun in 1921, and a testing plant was built in 1923, but com mercial usage has not been attempted. MILLING MET GRADING Fiber is graded according to ' g long and 28 inches in diameter .( tiles clamped to a central shaft agitate grades through the screen. One type tionary trommel in which the paddle; tions per minute. The tips of the p tingle, which causes the fiber to travel machines are so designed that the tro at 5 revolutions per minute and the } direction at ISO to 250 revolutions " make only one finished grade--that and the oversize is conducted to a sect ing. Thus, several trommels may opt newer mills the trommel is equipped which make one oversize and two un of grades may be made, and special blending. Sand and dust are remov fiat cleaning screens. Finished fiber 1 by air suction is conveyed to the store : CLA'SIFICATI Methods of grading asbesto? fiber b To determine with reasonable accurac grade and thus be able to modify gr standard testing machine is used! T standard test and thus avoid any con dependance upon trade names or de the standard testing .machine follow The machine consists of a nest- of : 24% by 14% inches and 3Vc inches in superposed one above the other. n 1. 2. 3. and 4. The bottoms of l .j : lie screen of the following specificatidiameter of wire, 0.105 inch. Box 2: 3: 10-mesh wire, 0.047 inch. Box 4 that fall through the three other boxe trays rests on a table to which an ecce gives a movement of l-ft-inch travel. To make a test, 16 ounces of asbestos is covered. The machine is run at tl minute at the shaft of the eccentric. : device this is kept going for exactly horizontal shaking movement. At th< that remains on each tray is weighed, asbestos fiber; the longest fiber nati whereas the shorter fiber, according to 2 and 3 or drops into the pan or low tained on the first screen and the less the grade and, therefore, the greater . * Ross, I. G., Work ched, p. -1'J. ASARCO ALV 0006317 ISTOS shell hr ahout % to 1 inch. They tiie ^ken rock toward the dis400 -00 revolutions per minute, .-ktreSted. Instead of the .Jumbo nis types of cyclones, which beat ie cyclone consists of a cast-iron >ed like ship propellers are driven of 1.700 to 2.000 revolutions per beaters revolve in the same direecontrolled by gates. The Torrey nbo, except 'that tlie axis of the SIXQ atrics generally are used, although type also are employed. Usual 0 12 feet long. Perforated steel n wire mesh. Screens with holes larger are used for scalping, and -y-second of an inch for the very ring from 3 to 24 meshes to the g fiber. . but the coarser rock fragments reen. The shaking action'brings -`dded-rock fragments, and it is tat will be described later. Thus, .cts--fines that pass through as .urged at the end, and fiber colgmeiits pass to the next fiberizing TIOV of a layer of rock fragments on tion '' oils that operate on the e op ,g of the suction hood is ,s the full width of the screen at ea of the narrow opening is the it converges, which ranges from fans produce the necessary vacis required to drive a fan giving !i a pipe 15 inches in diameter. n the screens, carries it through chambers, where the diminished 1 falL The dust-laden air from ers, and the fine materials that 11. where the longer fibers are grades are bagged and sold as ` XSS ide in developing a wet process ne claim that wet treatment inhiglier recovery. Experiments ant was built in 1923. but comL ; i j i j i i MILLING METHODS 69- c&Aomo Fiber is graded according to length in trommels about 8 feet long ancl 2S inches in diameter fitted with woven-wire cloth. Pad dles clamped to a central shaft agitate the fiber and force the shorter grades through the screen. One type of machine consists of a sta tionary trommel in which the paddles rotate at 400 to 900 revolu tions per minute. The tips of the paddles are twisted at a small anglej which causes die fiber to travel through the machine. Other machines are so designed tliafc the trommel rotates in one direction at 5 revolutions per minute and the paddles rotate in the opposite direction at 180 to 250 revolutions per minute. Some trommels make only one finished grade--that passing through the screen-- and the oversize is conducted to a second trommel for further grad ing. Thus, several trommels may operate in series. At one of the newer mills the trommel is equipped with two sizes of screen cloth, which make one oversize ana two undersize grades. Any number of grades may be made, and special grades may be obtained by blending. Sand and dust are removed from the graded fiber oh fiat cleaning screens. Finished fiber lifted from the cleaning screen by air suction is conveyed to the store room for bagging. CLASSIFICATION Methods of grading asbestos fiber by length have been described. To determine with reasonable accuracy the quality of fiber in each grade and thus be able to modify grading methods accordingly, a standard testing machine is used. The purchaser can rely oh." the standard test and thus avoid any confusion, that might ensue from depentlanee upon trade names or designations. A description of the standard testing .machine w follows f The machine consists of a.nest of four.wooden boxes measuring 2iy> by 1434 inches and 3y> inches in depth. The boxes, which are superposed one above the other, are numbered, from the top down, 1. 2, 3, and 4. The bottoms of boxes .1, 2, and 3 are made of metal lic screen of the following specifications: Box 1: y.-inch opening, diameter of wire, 0.105 inch. Box 2: 4-mesh wire, 0.063 inch. Box 3: 10-mesh wire, 0.047 inch. Box 4 is a receptacle for the fines that fall through the three other boxes. The nest of four boxes or trays rests on a table to which an eccentric with a throw of jjS inch gives a movement of ljVinch travel. . To make a test, 16 ounces of asbestos is put on the top tray, which is covered. The machine is run at the rate of 300 revolutions per minute at the shaft of. the eccentric, and by means of an automatic device this is kept going for exactly 2 minutes, giving the nest a horizontal shaking movement. At the end. of this'time the asbestos that remains on each tray is weighed. This gives the grades of the asbestos fiber; the longest fiber naturally stays on tne top trav, whereas the snorter fiber, according to its length, remains on screens 2 and 3 or drops into the pan or lowest tray. The more fiber re tained on the first screen and the less fiber in the pan, the higher the tirade and, therefore, the greater its value. If, for instance, a* * Rosa. J. O.. Work cited, p. 19. ASARCO ALV 0006318 70 ASBESTOS customer buys spinning fiber of the specification 4-7-4-1. it means that in a sample of. 16 ounces, representing the average of the lot shipped. 4 ounces will remain bn the top screen. 7 on the second. 4 on the third, and. finallv, 1 ounce will go through all the screens into the pan. He will evidently pay more for this material than for paper stock testing 0-0-10-6. This indicates that out of 16 ounces tested, nothing is retained on the first two screens. 10 ounces remain on the tliird. and 6 ounces go through the latter into the pan. Ir is evident that the figures of the test represent the proportion, in ounces, of the different lengths of fiber in a pound of asbestos. Samples for testing usually are taken at the grading machines every half hour. Owing to unavoidable variations in fiber as it comes from the nit, the quality of mill-run fiber usually is maintained a little higher tnan its designation. For many years each Canadian company'graded its fiber accord ing to its own standards and sold the products under its own trade designations. This practice led to much confusion in marketing be cause different mills employed similar marks for grades quite unequal in quality and value. It was frequently necessary for buyers to have samples "tested before placing orders. In 1931, producers in Quebec agreed upon a uniform classification of fibers whereby they are di vided into nine groups, and each group was divided into grades. Crude asbestos was defined as "hand-selected cross-vein material es sentially in its native or unfiberized form", and milled asbestos as "all grades produced by mechanical treatment of asbestos ore." Except for the verv lowest grades, which are based on the weight per cubic foot, all milled grades are based on the results of tests in the standard testing machine previously described. Boss47 gives a com plete description of the standard grades of Canadian^ asbestos as agreed upon in 1931: Crude asbestos Class ] Standard designation of j grade Description Group no. 1.... . Crude No. 1.............. Consists basically of crude ?4*`fnch staple and longer. Consists basically of crude H'inch staple up to i^-inch. Consists basically of unsorted crudes. ` Crudes sundry.................. Consists of crudes other th8n above specified. Milted asbestos Group no. 3........ Group no. 4. Group no. 5....... Group no. 6..... Spinning or textile fiber... TVaste. stucco or plaster... Consists of fiber testioe O-t-6-2 and orer. Consists of fiber testme below o-S-c-2 to and Includinf 0-1V5-9j5--5. Consists of fiber testinc below CMb-OK-5 to and Includint: 0-0-8-8. Consists of material testing below* o-O-S-8 to and including Group no. 7____ O-O-6I2-9V5. Coosists of material testing 0-0-5-11 and below, including material testing below 0-0-1-15 and specified as weighing Group no. 8____ ^35 pounds or less per cubic foot, loose measure. Group no. 9..... over 35 pounds per cubic foot, loose measure, and under <5 pounds per cubic foot, loose measure, and containing a preponderance of rock. Consists of such asbestos mill products weighing 75 pounds and over per cubic foot, loose measure. "Boss, J. C_ Work cited, pp. 50-51. 'itMILLING METHODS Subdivision of the prnups of mUh Croup no. Stand' Qt'etpficancih.. i No. 3. Textile and spinning fibers. No. 4. Shingle fibers. No. 5. Paper fibers. No. 6. 7\*aste, stucco, or plaster. No. 7. Refuse or shorts............. No. 8. Sand. No. 9. GraTel and stone. 3D 3F 3K 3M 3P. 3T 3Z 4D 4f 4K 4M 4R 4T a sr> 5F 5K SM 5R ST SZ 6D 6F 7D 7F 7H :M 7-20 7-25 7-30 7-35 5-40 5-45 8-55 -75 9 5 - ! j i 4j.- 3. 10- 0 0 0 0 0 0 ( 4 1 { 1 ' 1 i The fiber is packed in jute bags of J marked with the grade letter or r>"mb The high cost of transportation to i charges to markets render the sale of sho able. Spinning fibers are therefore tin Arizona deposits. The smaller mines ] almost exclusively. The rock is mineworkers on a contract basis. Cobbing is wav as in Canada. Three of the larger mines have millim equipped with crushers, cyclones, and fiber % to 2*4 inches long: Sn. ", to inch long; and No. 4, % inch ami less, cording to tests made with a standard In one of the smaller mills the rodcrusher followed by two sets of rolls. ' rated bv an. impact screen. The shortsmall fiberizing machine nml is cleaned feet long and 4 feet in diameter. ASARCO ALV 0006319 ros - specification. 4-7--t-l, it means 'eser'* g the average of the lot e tc :reen, 7 on the second, 4 '1 go tferough all the screens into .ore for this material than for indicates that out of 16 ounces two screens, 10 ounces remain glx the latter into the pan. It st represent the proportion, in *er in a pound of asbestos, aken at the grading machines dable variations in fiber as it -run fiber usually is maintained npanv graded its fiber accord; products under its own trade icn confusion in marketing bemarks for grades quite unequal ly necessary for buyers to have In 1931, producers in Quebec of fibers whereby they are dioup was divided into grades, selected cross-vein material esform", and milled asbestos as treatment of asbestos ore." ch are based on the weight per on the results of tests~in the escribed. Boss47 gives a comides of Canadian asbestos as `O* -criptloa call? of crude 3t-tach staple and lancer, cally of crude K-mch staple up to -h-inch. rally of uzisorted crudes, udes other than above specified. 9< 'er testing 0-r4-2 and over. her testing below 0-8-4-2 to and including er testing below 0-l5i-9H-5 to and Including iterial testing below (H3-8-8 to and including iterJal testing ft-0-5-11 and below, including ing below 0-04-15 and specified as weighing * less per cubic foot, loose measure, rh asbestos mill products as sand treiehine ids per cubic foot, loose measure, and under er cubic foot, loose measure, and containing :nce of rock. n asbestos mill products weighing 75 pounds t cubic foot. loose measure. MILLING METHODS 71 Subdivision of the groups of milled asbestos Group oo. Standard designation Guaranteed minimum shipping test of grades No. 3. Textile and spinning fibers.. No. 4. Shingle fibers.. No. 5. Paper fibers.. No. 6. Waste, stucco, or plaster.. No. 7. Refuse or shorts............... No. 5. S3nd.............. No. 9. Gravel and stone.. 3D 84-1-1. 3F 7-7-lH-H. 3K 4-7-4-U 3M 2-9-4-1. 3R 2-84-2. 3T 1-9--4-2. 3Z 0-84-2. 44DF 0-5-104. 0-3-12-1. 4E 04-9-3. 44MR 04-8-4. 0-3-94. 4T 4Z 00--124-1-90544. -5. 5D 0-54-1054*5. 5F 044-9*4-8. 5E 0-0-124. 5M 0-0-11-5. 5R 0-0-104. 55ZT 0-0-9-7. 0-0-84. CD 0-0-7-9. 6F 0-0-654-9H. 7D 0-0-5-11. TF 0-04-12. 7S 04-3-13. 7E 0-0-2-14. 7M 7-20 7-25 7-30 7-35 I ' 0-0-1-15. 20 pounds 25 pounas 30 pounds 35 pounds per per per per cubic cubic cubic cubic foot. foot, foot, foot, loose loose loose loose measure, measure, measure, measure, 8-40 S--45 8-55 S-75 40 45 55 75 pounds pounds pounds pounds per per oer per cubic cubic cubic cubic foot, loose foot.loose foot. *.ooe foot, loose measure, measure, measure, measure, 9 75 pounds and over per cubic loot, loose measure. The fiber is packed in jute bags of 100 or 125 pounds capacity marked with the grade letter or number and the manufacturers name. AXIZONA The high cost of transportation to railways and 'heavy' freight charges to markets render the sale of shorter Arizona fibers'unproBt- able. Spinning fibers are therefore the principal products of the Arizona deposits. The smaller mines produce hana-cobbed crudes almost exclusively. The. rock is mined and cobbed by the same workers on a contract basis. Cobbing is conducted in much the same way as in Canada. Three of the larger mines have milling facilities. The largest mill, equipped with crushers, cyclones, and screens, produces No. 1 mill finer % to 2Vo inches long; No. 2, % to % inch long; No. 3. Vs t0 3s inch long; and No. 4. % inch and less. The produces are graded ac cording to tests made with a standard Canadian testing machine. In one of the smaller mills the rock first passes through a jaw crusher followed by two sets of rolls. Two grades of fiber"are sepa rated bv an impact screen. 'Die shorter asbestos is treated with a small fiterizing machine and is cleaned and graded ill a trommel 16 feet long and 4 feet in diameter. ASARCO ALV 0006320 72 asbestos Another small mill produces five grades of spinning fibers and a shimrle stock. No grades shorter than shingle stock can be sold profitably. A considerable quantity of rock containing spinning-fiber veins, which are difficult to cob by hand, are treated in these mills and yield what is known a? mechanically cobbed crude fiber, an anomalous designation, accordin': to the Canadian definition of crude, which includes only hand-<-obbed fiber. The claim is made, however, that the crude fiber can be graded by machine more accurately than by hand. VERMONT The asbestos-bearing rock quarried near Eden. Vt.. first is crushed to 5- or O-inch size in a 28- by 36-inch jaw crusher and then dis charged to a 36-inch belt conveyor, which carries the material to a 1,000-ton storage bin. AYhen taken from storage, it is crushed to 3-inch size in a 13- by 30-inch jaw crusher. The product is split to two 41.0* fi.v 40-foot rotary driers. A trommel with 34. inch openings precedes the final crushing unit--a 512-foot Symons cone. The material that passes through the trommel is combined with the crusher product and conveyed to a. second storage bin. The product of the tertiary crusher is treated in a series of Jumbos or fiberizers like those used in Quebec, and the fiber is recovered byscreening and air suction. Oversize material passing the hoods is conveyed to a second series of fiberizers. The fiber picked up by air suction in the collectors is further screened, passed through dust re movers and graders, dropped into bins according to length, and sacked in 100-pound burlap bags. The principal" products manu factured are shinsrle stock testing 0-2-10-4: millboard, paper, and molded brake-lining fiber testing 0-0-10-6 or 0-0-S-8: and material suitable. for roofing, paints" plastics, molded products, and boiler covering testing "0-0-5-11. Equipment was installed in 1936 for salvaging the shorter grades not "heretofore recovered, and additional grades now marketed include 0-0-2-14. 0--0--1--15, 0-0-0-16. "no test" and "floats." Special brake-Iinim: fibers are prepared at times. Virtually no crude or spinning fibers are produced. The mill capacity is upward of 100 tons of rock an honr. The demand for the products has more than tripled during the past 4 years. Figure 8 shows the mill as it appeared in 1936. UNION or SOUTH AFRICA CHRYSOTTLE At the New Amianthus, mine. Barberton district. Eastern Trans vaal, long-fibered chrysotile is hand-sorted and graded by natives as A and B, fiber over lVs inches' long and fiber 3/ to lVs inches long, respectively: both are designated as crudes. A third grade. E, con sisting of hand-selected fiber down to y2 inch long might be classed as crude. Bock bearing the shorter fibers is crushed, dried, and reduced by Tolls. The product of each set of rolls is sieved over 10-mesh screens, the fines going to waste. After passing through four sets of rolls the product is virtually pure fiber except"for dust adhering to it. The Bureau of Mines FliitKE b.--Mill o( the Vermont .'.soestos O ASARCO ALV 0006321 rSTOS e grades of spinning fibers and a, tha shingle stock can be sold Co.__.min" spinning-fiber veins. re treated in these mills and yield tbbed crude fiber, an anomalous idian definition of crude, which 'he claim is made, however, that lacliine more accurately than by {i >NT d near Eden, Vt., first is crushed -inch jaw crusher and then diswhicn carries the material to a from storage, it is crushed to crusher. The product is split driers. A trommel with Sw ishing unit--a 5t4-foot Symons ougn. the trommel is combined ed to a. second storage bin. The eated in a series of'Jumbos or . and the fiber is recovered by material passing the hoods is ?rs. The fiber picked up by air reened, passed through dust re bins according to length, and The principal" products ntanu- 0-2-10--i: millboard, paper, ng O-O-l't-6 or 0-Q-8-8: and ts, plastics, molded products. 11. Equipment was installed ades not heretofore recovered, d ' -me 0-0-2-14. 0-0-1-15, 1 .oial brake-lining fibers crude or spinning fibers are rd of 100 tons of rock an hour, e than tripled during the past appeared in 1936. | : Bureau of Mines Bulletin AFEICA ,e srton district. Eastern Transorted and graded by natives ,nd fiber ^ to inches long, tides. A third grade, E, con14 inch long might be classed FIUCKE s.-Miil ot the Vermont Asbestos Corporation near Eden, Vt. uslted, dried, and reduced by s sieved over 10-mesh screens, through four sets of rolls the ior dust adhering to it. The L i ASARCO ALV 0006322 MILLING METHODS 73 asbestos is passed through a fiberizer to beat out the dust, then over a dust sieve, and finally over grading sieves. Two principal mill grades are made: F, one-rourth to one-half inch; and G, one-fifth to one-fourth inch.' Grade F corresponds to Canadian fiber testing 0-414-10-1%. The milled fibers are principally shingle and paper stocks!" The mill has a capacity of 6.000 tons of rock a month. At the Munnik-Myburgh mine in the same district four grades of hand-cobbed chrvsocile fiber are designated as follows: IXL. over three-fourths inch; XL, one-half to three-fourths inch; X. one-fourth to one-half inch; and XX, one-eighth to one-fourth inch. Handcobbed fiber is graded in shaking screens. Short fiber is treated in a milfwith an elaborate flow sheet. Dried and crushed rock is passed through a series of rolls followed by grading screens. All five products obtained are passed through a regrading plant. The grades and their values, as shown on a Canadian standard testing machine, are as follows: Ml 2-11-2-1 I M4 O-O-Sj-Ti M20-S1-6-H Mo MS 0-3-10-3 | The milled grades constitute about' 95H percent of the total fiber recovery. CROCIDOLITE Methods of milling and grading crocidolite vary greatly in differ ent localities. In the Southern Belt of the Cape Provinces the work ings are numerous, and many are relatively small. Ac the smaller workings the fiber is all hand-cobbed. In many places it is handsorted into grades according to length, but at the larger workings the hand-cobbed asbestos is~graded by machinerv. .A hand-turned trommel made of perforated sheet iron or covered with wire netting usually is employed. The cobbed fiber front a series of workings may be shipped to a central screening plant where all asbestos onehaff inch long or over is recovered, and the minus one-half-inch product is taken to a mill for further crushing and grading. At one mill the rolls travel at slightly different speeds so as to subjecc the fiber to a tearing action. Double grading trommels sometimes are used. The innercylinder has one-fourtli-inch holes and the outer one-eighth-inch. Material passing the outer cylinder is waste: the oversize from the outer cviinder is designated grade S3 and the oversize from the inner cylinder is grade S. The following grades are produced: E. Over 2-inch cobbed fiber. D. l?4-iuch to 2-inch cobbed filler. C. 1*4-inch to 1%-inch cobbed fiber. B. %-lnch to l*4-inch cobbed fiber. A. ^i-inch to ?4-mch cobbed fiber. S. %-inoh to %-inch milled fiber. SS. Shorts. *5-inch to *4-ineh niilled fiber. In the Northern Belt, material over three-fourths inch long is hand-cobbed. For many years the mill grades were not standard ized and the companieshad difficulty in "marketing their products. Later, a large mill was erected at Knruman. and the grades manu factured there were established standards that offered such decided 5f ASARCO ALV 0006323 74 ASBESTOS marketing advantages that other producing companies adopted them. In this mill, rock carrying the shorter fibers is passed through "crushers, heavy rolls, and disintegrators. The filler thus separated is classified on grading screens. The following grades.are made: ES. Over Iti-im-li haml-eohhed fiber. No. 1. Viuch to lVi-iucb hand-cobbed fiber. discolored Slier. No. 2. :N-iiK'h to 91-inch milled fiber. No. 3. 9s-inch, or under, milled fiber. Also, 2 grades of plus 91-inch Of the total fiber recovered, about 13% percent is liand-cobbed and SGii percent milled. In both the Northern and Southern Belts about9 percent of the total fiber is of spinning grade. Crocidolite of the Petersburg district, Transvaal, is passed through rolls, fiberizers. and grading trommels. Four grades are produced: B. Over 1% Inch. A. % inch to 1% inch. S. % inch to % inch. Paper grade, % Inch to % inch. AMOSITE Because of its unusual length, most of the amosite produced is hand-cobbed. The fiber thus freed from adhering rock is passed through a series of rolls and disintegrators and then graded on shaking screens or trommels, usually into three grades. No. 1 is spinning fiber: no. 2 is used in the manufacture of rope, felts, and similar products: and no. 3 is used for asbestos-cement products such as roofing slates and corrugated sheathing. The fiber is classified both according to length and color. The colors range from whitish gray to yellowish; the gray shades are considered the best Most of tlie mills are small. RHODESIA The Rhodesian asbestos industry is centered at the large chrysotile mines of Shabani. To avoid damage to the fiber, as much or it as possible is separated from the rock close to the working face; hence, the liand-cobbing and bagging of crude fiber is an important part of quarrying and mining operations. Each cobbing boy recovers about 1.300 pounds of fiber a shift in. open quarries and 1.000 pounds a shift in stopes. The cobs are said to average 40 to 50 percent fiber. The quarry rock first is broken in jaw crushers and rolls, and the products are sorted on picking belts into three groups: (1) Rock conraining little or no fiber. (2) rock containing large seams of fiber, and (3) fines and rock carrying small seams of fiber. Product 1 is left on the belt and conveyed to the waste heaps, product 2- is carried on a_ second belt to the cobbing sheds, and product 3 is conveyed by a third belt to the mill. Hand cobs from both the cobbing shed's and the quarries or stopes are fiberized and graded in one mill, and the fiber-bearing rock is reduced in another. Some maintain that when fiber-bearing rock is kept wet until it reaches the mill it suffers less damage ana is in better condition for milling than when it is handled and rehandled dry. After primary i j ; ` i ! j : j J i MILLING METH crushing m the mill, the rock is dried eit mem or in rotary driers in winch j wood fires are iii direct contact v \ reduced in a series of small erindin p. Fiber is separated from rock with sha in the same manner as in Canada. Und in the pans and passes through the ; Fiber carried in the air current is depc and the air passes on through the exh; outlet. The asbestos is taken to a. gra. further from dust and separated intc Grading is done in hexagonal trommel: Cobbed asbestos is fiberized, cleaned, the equipment is modified to handle loi In the Shabani area, the tonnage of To Zy4 percent of the total rock mint fiber averages about 4 percent of the infer that the rock is leaner than in Q 6 percent, because short-fiber material tons in Quebec is discarded as waste ir Few data are available on the "rad the proportion of each grade. From fiber, and most of the remainder is than paper stock cannot be bandied y transportation expense to markets, nos. 1 and 2, are the only grades quot< reports. At the King's and Gatlis' mines asbestos is recovered by hand-eubbin ketable fiber obtained is 0.7 to 1.2 per RUSSIA In Russia, crude asbestos is sc Canada; but, with increasing n. .a dined and a larger proportion of the For many years the fiber was conce quarries.* Although recoverable fibi of total rock quarried, the eliminatior so raised the grade that mill feed a\ fiber. During recent years median placed hand, methods to a large exte by hand-sorting on picking belts af "The preliminary stages of rock in one of the newer mills, the "Gig 1932. Rock from the quarry is com that to a no. 9 Gates gyratory crur 6-inch size. It discharges to a pick: of the primary feed containing too thrown out as waste rock. The asb 1y2- to 2-inch size in two no. 7 Gate to "heavy shaking screens. Tiie ov to picking belts, where more barrer 1 ASARCO ALV 0006324 T 3T0S roducing companies adopted them, sho*** -- fibers is passed through rat The fiber thus separated he following grades.are made: 1 fiber. Also, 2 grades o plus 94-inch 113% percent is hand-cobbed and irthern and Southern Belts about ming grade. district, Transvaal, is passed ing trommels. Four grades are TE :ost of the amosite produced is i from adhering rock is passed utegrators and then graded on ily into three grades. No. 1 is manufacture ot' rope, felts, and or asbestos-cement products such eathing. The fiber is classified The colors range from whitish are considered *the best. Host Ul ; cei. ed at the large ohrysotile :e to the fiber, as much or it as lose to the working face; hence, rude fiber is an. important part s. Each cobbing boy recovers open quarries and 1,000 pounds o average 40 to 50 percent fiber, jaw crushers and rolls, and the ito three groups: (1) Rock conontaining large seams of fiber, 11 seams of fiber. Product 1 is -aste heaps, product 2 is carried i, and product 3 is conveyed by s from both the cobbing sheds ;d and graded in one mill, and nother. iring rock is kept wet until it e and is in better condition for rehandled dry. After primary MILLING METHODS 75 crushing in the mill, the rock is dried either with steam-heated equip ment or in rotary driers in which the products of combustion from wood fires are in direct contact with the rock. The dried rock is reduced in a series of small grinding pans operating like pug mills. Fiber is separated from rock with shaking screens and air suction in the same manner as in Canada. Undesirable brittle fiber is ground in the pans and passes through the screens with the waste rock. Fiber carried in the air current is deposited in a centrifugal settler, and the air passes on through the exhaust fan and dust trap to an outlet. The asbestos is taken to a grading mill, where it is cleaned further from dust and separated into the various market grades. Grading is done in hexagonal trommels. Cobbed asbestos is fiberized, cleaned, and graded in a mill in which the equipment is modified to nandle longer fiber. In the Shabani area, the tonnage of cobbed fiber ranges from to 3% percent of the total rock mined. Total milled and cobbed fiber averages about 4 percent of the rock quarried. One must not infer that tne rock is leaner than in Quebec, where recovery is about 6 percent, because short-fiber material amounting to many thousand tons in Quebec is discarded as waste in Rhodesia. Few data are available on the trades produced at Shabani or on the proportion of each grade. From 25 to 30 percent is spinning fiber, and most of the remainder is shingle stock. Fiber shorter than paper stock cannot be handled profitably because of the heavy transportation expense to markets. The longest spinning fibers, nos. 1 and 2, are the only grades quoted in the United States market repAotrtst.he King's and Gatlis' mines in the Hashaba district the asbestos is recovered by hand-cobbing only. The tonnage of mar ketable fiber obtained is 0.7 to 1.2 percent of the rock quarried. RUSSIA In Russia, crude asbestos is sorted in the quarry and cobbed as in Canada: but, with increasing mechanization, hand cobbing has de fined and a larger proportion of the fiber is prepared mechanically. For many years the fiber was concentrated by nand-sorting in tile quarries. Although recoverable fiber averages about 4V-> "percent of total rock quarried, the elimination of barren rock by hand-sorting so raised the grade that mill feed averaged about 22 'percent of the fiber. During recent years mechanical mining equipment has re placed hand methods to a large extent and the fiber is concentrated by hand-sorting on picking belts after the rock is crushed. *The preliminary stasres of rock treatment are exemplified best in one of the newer mills, the "Giganc", which began operation in 1932. Rock from the quarry is conveyed to a storage bin-and from that to a no. 9 Gates gyratory crusher, which reduces it to about 6-inch size. It discharges to a picking belt, where about 20 percent of the primary feed containing too little fiber to justify milling is thrown out as* waste rock. The asbestos-bearing rock is reduced to 114- to 2-inch size in two no. 7 Gates gyratory crushers discharging to heavy shaking screens. The oversize from the screens passes to nicking belts, where more barren rock is eliminated. The good ASARCO ALV 0006325 76 ASBESTOS rook from the picking: belt is reduced to about i-inch size in a jawcrusher and joins the undersize from the shaking: screens in a wet""srorage bin. whence it passes to three rotary driers, which reduce the water content from ahout S to 1 or 2 percent. The product is conveyed to the dry-storage bin. The most noteworthy feature of the preliminary milling stage is the concentration on picking belts. Because the serpentine tends to break cleanly along the fiber veins, effecting a more or less dis tinct separation of barren and fiber-bearing rock, conditions par ticularly favor this method of concentration. Of the original mill feed, co'nsisting of 2.400 tons a day, about 1.440 tons are eliminated as waste, leaving only 960 tons for the later milling processes. Thus, picking belts save operators a great deal of useless milling. In the more advanced milling stages the dried rock is passed over heavy shaking screens, from which four products are obtained: (1) Fiber removed by suction fans, (2) oversize rock conveyed to a set of rolls. (3) middlings that bypass the rolls and are carried to the next screen, and (4) fines conveyed to a Humboldt disintegrator. By means of a series of such rolls, screens, suction pipes, and dis integrators, virtually all of the fiber is recovered. Fiber from the collecting hoppers is sent to a series of shaking screens for cleaning. The cleaned fiber is collected again by suetion'fans and classified by length in slowly rotating grading trommels. The older mills employed a typically Russian method of milling. The rock was reduced in a series of rolls, and part of the fiber was separated from rock with trommels: the major separation, however, was made on inclined planes provided with suitable gaps. The fiber dropped through the gaps, and the rock fragments jumped over them. Ru Keyser46 has described milling processes in some detail. A large new mill designed to handle 2.000,000 tons of rock an nually and produce 80.000 tons of fiber in six grades was nearing com pletion in 1934. This mill will give Russia- a total milling capacity of approximately 175,000 tons of fiber a year. Little information is available regarding the grades produced and the percentage of each grade. _ Estimates made in 1931 indicated that fiber one-third inch or more in length constituted about 30 percent of the total output. Since that date, with increasing factory ca pacity for the manufacture of asbestos products, probably a larger proportion of the shorter grades is produced. Grades entering the German market in 1929 were designated as follows: Grade 0. 1V< inch or longer. Grade 1. % inch to l*-j inches. Grade C. ^ to inch. Grade 3. 9s to 9g inch. Grade 4. % to % inch. Grade 5. Less than inch. Price quotations for Russian fiber in the American market include Crude No. 1. Crude No. 2, Crude No. 3. and shingle stock. Begin ning July 1935. a new grade, designated Crude AA. was placed on the'market. Evidently it is the nighest grade produced, because it was quoted at $450 a ton.** ** Ru Keyser, Welter A.. Asbestos Milling in the Urels: Eds. and Min. Jour., vol. 134, no. 1C. October 1933, pp. 415-419. MILLING MET! CYPRUS In Cyprus, the rock bearin': cl- o that it breaks down readily inn .s hand-cobbed fiber are obtained. Ko. hand methods is screened to eliminat* (7/10 inch) and fines under 5 mm product, which averages about one-si: is sent to the mills. The mil! feed i sfuhratkhienrg tsocrereemnsovaendduthset afinbdertoreccolavsesr?ii asbestos recovered constitute; about and virtually the entire production is Milled asbestos is graded into tlire fines. The standard grade, designa include about 75 percent, of the p is exported. Twelve mills were repot aggregate capacity is 25.000 tons of fi They are operated during the dry set AUSTRAI The Lionel plant in Australia p numbered in the reverse order frui smaller numbers are applied in the est grade produced, includes fibers : f/2-inch: ^o. 3, about 1 inch: and N ANTHO?KYIIT"r Anthoph;. t!*(o. -. .- of a small way it.............. = been operated in ginia. and "Washing! - --iut ..itaii; - a lorg is,asbestos, fiberization .... c n processes. The fiber is nm.h >.cak severe treatment is to be avoided. In one mill operated a few year in a gvratorv crusher, whence it \ with air suction for carrying off t followed by reduction in' a double opposite directions. The fiber war largement in the suction pipe ret? rent, permitting heavy fragments fragments were returned through circuit. The fiber was clarified _ In another mill the dried rock i followed by a set of rolls. The in a hammer mill equipped wit terial is returned to the nberizer. > and the fiber is conveyed to a bi fiber is packed in 100- or 200-pot processes are employed in other m ASARCO ALV 0006326 > ah 1-inch size in a jaw e sl .ng screens. in a wetotarv driers, which reduce 2.-percent. The product is >reliminarv milling stage is cause the* serpentine tends ffecting a more or less disiring rock, conditions parition. Of the original mill at 1.440 tons are eliminated er milling processes. Thus, of useles*s milling, le dried rock is passed over products are obtained: (1) size rock conveyed to a set oils and are canned to the a Humboldt disintegrator, ens, suction pipes, and disrecovered. Fiber from the taking screens for cleaning, xtion fans and classified by .els. Russian method of milling. and part of the fiber was major separation, however, th suitable gaps. The fiber ck fragments jumped over lg processes in some detail. 2.000,0n<) tons of rock ansix grades was nearing comsia ral milling capacity yeai. ig the grades produced and made ill 1931 indicated that instituted about 30 percent vith increasing factory cau'oducts. probably a larger need. Grades entering the as follows: ie American market include and shingle stock. Begin: Crude AA. was placed on ,t grade produced, because rals; Eng. and Min. Jour., vol. 134, 1r iI MILLING METHODS 77 CYPRUS In Cyprus, the rock bearing chrysotile asbestos is so decomposed that it breaks down readily into small sizes. Small quantities of hand-cobbed fiber are obtained. Rock reduced in the quarry by hand methods is screened to eliminate barren material over IS* mm (7/10 inch), and fines under 5 mm (1/5 inch); the intermediate product, which averages about one-sixth of the total quarry output, is sent to the mills. The mill feed is crushed and passed'over flat shaking screens and the fiber recovered by air suction. It is treated further to remove dust and to classify it according to length. The asbestos recovered constitutes about 314 percent of the mill feed, and virtually the entire production is short fiber. Milled asbestos is graded into three classes--standard, shorts, and fines. The standard grade, designated "shingle stock", is said to include about 75 percent of the production^ The entire output is exported. Twelve mills were reported in operation in 1935. Their aggregate capacity is 25,000 tons or fiber a year of 6 working months. They are operated during the dry season only. AUSTRALIA The Lionel plant in Australia produces four grades, which are numbered in tne reverse order from that generally practiced: the smaller numbers are applied to the shorter fibers. * No. 1. the low est grade produced, includes fibers about 14-inch long: No. 2, about 14-inch: ho. 3, about 1 inch: and ho 4, 2 inches and over. ANTHOPHYLLITE MILLING Anthoph;-. ihi'e. -t of amphibole asbestos, has been mined in a small way n. -i: ' `ates for many years. Small mills have been operated in - -j.itana, North* Carolina. Oregon, Vir ginia. and Washing!- ' ' a large percentage of the rock treated is asbestos, fiberizatiou a.-' classification are the principal milling processes^ The fiber is mu-.h weaker than chrysotile, and therefore severe treatment is to be avoided. In one mill operated a few years ago the dried rock was broken in a gyratory crusher, whence it went to a hammer mill equipped with air suction for carrying oil the loose fiber. This process was followed by reduction in' a double-cage mill, the cages running in opposite directions. The fiber was removed bv air suction: an-en largement in the suction pipe retarded the velocity of the air cur rent. permitting heavy fragments of unopened fiber to fall. These fragments were returned through a trap to the cage mill in closed circuit. The fiber was classified with vibrating screens. In another mill the dried rock is first reduced with a jaw crusher, followed by a set of rolls. The crushed asbestos rock is fiberized in a hammer mill equipped with an air separator. Coarse ma-` terial is returned to the fiberizer. dust is collected in a dust chamber, and the fiber is conveyed to a bin that feeds into a packer. The fiber is packed in 100- or 200-pound sacks. Modifications of these processes are employed in other mills. 134342*--37------8 ASARCO ALV 0006327 78 ASBESTOS T" PRICES Anthophyllite mined in Harford County. Md.. is peculiarly suited for the manufacture of filters that resist the action of chemi cals. It undergoes special treatment, including careful hand selec tion and washing in acids. MARKETING Asbestos is used in so many diverse products that its markets are numerous and widespread. It is used extensively in the United States. England. France. Germany. Belgium. Italy. Netherlands. Spain.' Russia, and Japan. The last country has become an important buyer of roofing-grade asbestos. Russia at one time exported almost its' entire production, but recently it has become an important manu facturer of asbestos products. Many other countries use smaller quan tities. With greater diversity in use, expansion of automobile pro duction, development of new types ox building materials, and stronger demands for heat-insulation material, the consumption of asbestos has increased steadilv. In recent years, mineral, slag, and glass wools have increased in importance as insulation, and al though generally used in fields other than those in which asbestos is employed, they are replacing asbestos to some extent. Some'fiber is'handled by agents or jobbers.1 but most of it is shipped direct from mine to consumer. Usually samples are sub mitted and fiber length and quality are guaranteed. The larger manufacturers of asbestos products nave their own testing machines and can check the producer's classification. The producer should be familiar with manufacturing conditions in order that he may prepare the material to suit each particular use. Canadian asbestos generally is preferred by users in the United States, although African and' Russian fibers may be substituted for many uses. Considerable quantities of the latter fibers are mixed with' the Quebec product The principal Canadian producers sell direct to consuming indus tries and also to dealers and agents who distribute it to consumers. Sales frequently are made to consumers only after they have examined and approved samples submitted by dealers or producers. Canadian firms sometimes supply European customers with trial consign ments of several tons, particularly if they are introducing new products. Asbestos is sold in 100-pound or 125-pound bags on a short-ton basis, bags included. Quotations are f. o. b. mines. The weight of a given volume varies with the length of fiber as the longer fibers are bulkier. The volume of a short ton ranges from 60 to 90 cubic feet. A minimum carload of fiber is 20 tons, and of refuse and shorts. 30 tons. _ Settlement; usu'ally are made on the basis of 2 per cent discount within 10 days, or 30 days net. Before the World War. Hamburg'was the principal marketing center, but since that time New York has become the most important. The larger producers now have offices in New York, Hamburg, Lon don, ana other large cities. Market requirements are based principally on fiber length, but strength, flexibility, color, chemical composition, and cleanliness may have an important bearing on use. The principal market outlets are indicated in the following brief summary of uses. The longer and more valuable asbestos upward from about $70 a ton. are i brake linings, textile fabrics, aiiu as'. * grades, ranging from about $25 to $70 a b ing rigid asbestos-cement shingles, lumber Still shorter fibers are used in manufacti and the lowest-grade fibers are emploved cold molded products, and fillers. European imports from Africa are liai or agents. The importers pay cash or op and sell on credit to manufacturers. Tn directly from producers because they a to 6 months' credit, and importations a a basis. The Canadian standard testir extent in Africa. Several of the largest asbestos orgai type; that is, they mine and mill the finished products. At least three larj States are of this type, each having mi in the United States. Turner & Newal the asbestos production of Rhodesia an of South Africa. The company has 2( tories in England. The Russian indu; State controls both production of raw i finished products. Because of this coi Russian production never enters the op. Most of the world supply of raw asb< hands, and distribution is conducted laboration with buyers, many of^whoi ized concerns. Hence, new producers are not likely to dislocate the market organizations sometimes have difficult consumers of asbestos ordinarily e vance of actual needs. _ Central, .d makes possible the establishment of n & Newell, Ltd., having control of ' Rhodesia, was able in 1931 to consumi whereby orders were apportioned bet the market stabilized on a basis satis PRICE! Prices of Canadian asbestos have past 15 years. In 1920. because o rocketed'to unprecedented heights, than $3,000 a ton. In 1921, the pric. amount! and bv 1925 the highest gr: one-eighth of the price received in 1! except for 1933 to 1936. the average ] received by producers as reported t Since 1932 the Canadian figures, u in enough detail to show values by f average price quotations as given in ASARCO ALV 0006328 County, lid., is peculiarly hat - 'sc the action of chemiinc ng careful hand selec- m products that its markets are a extensively in the United Belgium. Italy, Netherlands, .ntry has become an important a at one time exported almost s become an important manttier countries use smaller quanexpansion of automobile pro of building materials, and material, the consumption of :ent yearsj mineral, slag, and tance as insulation, and aithan those in which asbestos i to some extent, r jobbers,'but most of it is \ Usually samples are subare guaranteed. The larger e their own testing machines ition. Tlie producer should tions in order that he may liar use. rred by users in the United ibers may be substituted for the latter fibers are mixed I di to consuming indus0 d. oute it to consumers, nly after they have examined lers or producers. Canadian :comers with trial consignthey are introducing new -pound bags on a short-ton f. o. b. mines. The weight 1 of fiber as the longer fibers i ranges from 60 to-SO cubic 20 tons, and of refuse and made on the basis of -2 pernet. as the principal marketing ; become the most important. New York, Hamburg. Lon- :ipally on fiber leugth. but josition, and cleanliness may he principal' market outlets lary of uses. } PRICES 79 The longer and more valuable asbestos crudes and fibers, ranging upward from about $70. a ton, are used in manufacturing woven brake linings, textile fabrics, and asbestos packing. The next lower grades, ranging from about $25 to $70 a ton, are used in manufactur ing rigid asbestos-cement shingles, lumber, and corrugated sheathing. Still snorter fibers are used in manufacturing paper and millboard, and the lowest-grade fibers are employed in heat-insulating cements, cold molded products, and fillers. European imports from Africa are handled principally by dealers or agents. The importers pay cash or open a credit in South Africa and sell on credit to manufacturers. The latter concerns do not buy directly from producers because they are accustomed to buy on 3 to 6 months' credit, and importations are not made easily on such a basis. The Canadian standard testing machine is used to some extent in Africa. Several of the largest asbestos organizations are of the vertical type; that is, they mine and mill the raw materials and fabricate finisned products. At least three large companies in the United States are of this type, each having mines in Canada and factories in the United States. Turner & Newall, Ltd., controls nearly all of the asbestos production of Rhodesia and much of that of the Union of South Africa. The company has 20 large asbestos-products fac tories in England. The Russian industry is also of this type; the State controls boch production of raw materials and manufacture of finished products. Because of this condition, a substantial part of Russian production never enters the open market. Host of the world supply of raw asbestos is in exceptionally strong hands, and distribution is conducted in close and sympathetic col laboration with buyers, many of whom are also strong, well-organ ized concerns. Hence, new producers and new sales organizations are not likely to dislocate the market seriously. Furthermore, new organizations sometimes have difficulty in finding a market because consumers of asbestos ordinarily place'orders 12 to 18 months in ad vance of actual needs. Centralized control by large units also makes possible the establishment of marketing agreements. Turner & Newall, Ltd., having control of virtually the entire output of Rhodesia, was able in 1931 to consummate an agreement with Russia whereby orders were apportioned between European consumers and the market stabilized on a basis satisfactory to all concerned. PEICES Prices of Canadian asbestos have fluctuated greatly during the past 15 years. In 1920, because of war stimulation, prices sky rocketed "to unprecedented heights. Crude No. 1 selling for more than $3,000 a ton. In 1921, the price dropped to less than half that amount, and bv 1925 the highest grades were selling for only about one-eighth of tlie price received in 1920. The following table shows, except for 1933 to 1936, the average price per short ton. f. o. b. mine, received by producers as reported to the Quebec Bureau of Mines. Since 1932 the Canadian figures, unfortunately, are not presented in enough detail to show values by grades, and for these later years average price quotations as given in Mineral and Metal Markets are '! ASARCO ALV 0006329 80 asbestos used. Tiie latter figures. however, are generally very much higher -than figures for actual sale? as given by the Quebec Bureau of Mines. .1 rrrno'' vnlur per short Ion of nshcstns fold in Canada, J02I--3G: Year Crude No. 1 1021...................................................... in *-i lli'K iy3n................... .............................................. 1031.................................................................. ............................................................ ......................................................................... im...... ........................................................... fl. 2SI.32 <US. 6S 472. GO 365.07 364. Wi 371.51 423.05 534. $7 557.33. 430.44 43L45 396.94 437.50 45a 00 yrj.oo MO. 00 Crude No. 2 Spinning fibers | ; Shlnjle Slock ; Millboard ! and paper | stock ! SUC.91 265.32 237.29 ` 215.27 206.12 229.02 249.59 296. C5 331.82 235.44 216.35 192.43 206.25 212.50 212. 50 21150 S2C3.09 317.71 123.37 no. si 100.43 13a 22 129.32 14S.71 177.30 141.52 107.22 91.36 100.20 112.5<i 112.50 US. 75 1101.75 ; 81.00 57.05 45.12 50.78 5SlC2 64.80 73.80 75.26 70. SS.72 49.64 52 71 55.00 60.00 60.00 133L 19 >2L65 * 22.01 >19.64 31.03 33.88 37.82 38.73 38.56 35.33 >34.66 >30.84 >32.71 >35.00 >35.00 >35.00 * Fieuresfor iy2i-32from Quebec Bureau of Mines; for 1933-3G, average of quotations, Mineral and Metal .larueis. - Pai*r and others, s Paper cn>. Price trends are shown graphically in figures 9 and 10. PRICES Average quotations for Vermont asl AfartU. are Wn m the fo Prices of Vermont asl Year chiocle stock Paper stock Crr* HC-Ct i ----------------ij-- j ...................... $50.71 42.92 ...................... 42.92 $33.00 I 32.92 1 l ?2G.OO 1 193 SO.*/) 15 193 2th 25 ij 192 *s nflri The following table shows 1>;'1CCS ton. average quotatic lI Pieces 9.--Average -valu* per short ton of Canadian crudes and spinning fibers. 1921-35. Data for 1921-32 from Talue ot sales compiled by the Bureau of Mines, Province of Quebec. Data for 1933 to 1935 from price quotations in Mineral and Metal Markets, ASARCO ALV 0006330 s i ffep--ally very much higher 7 fir .ebec Bureau of Mines. w told in Canada, JDS1-381 Shisdd stock Millboard and paper stock jiol :j SI 00 57.05 15.12 50.78 58.62 64.80 78.SO 75.26 70. M 58.72 49.64 52.71 55.00 60.00 60.00 '$32.19 ' 22.65 '2201 '29.64 31.03 33.88 37. $2 38.73 38.56 3133 I34.S nasi *3271 '3100 '3100 *3400 -30. avrnie at quotations. Mineral and Metal figures 0 and 10. ? PRICES 81 Ftouns 10.--A.verage value per short too of Canadian <hingle. millboard, and paper 1021-35. Data tor 1021-32 tmm value of sale* compiled by the Bureau of Mine*. Province of Quebec. Data for 1033 to 1035 from price ;uocatiOD5 in Mineral and Metal Markets. Figures (or millboard and puper prior to 1925 represent paper aud oruers. Averaae quotations for Vermont asbestos, as given in Mineral and Metal Markets, are shown in the following table. Prices are per short ton. f. o. b. mines. Prices of Vermont asbestos, 1031--38 Year 1011............... 1912.... ........ ion ohinete Paper stock stock $50.71 $35.00 44229922 3292 Cement j stock fi Year < $20.00 i 1QM 20.1/0 1 20.25 i loss................ Sbincle stock $4100 16.25 47.50 Paper Cement stock Slock $35.00 35.00 35.00 $23.00 23. U0 23.00 The following table shows prices of Rhodesian ancl Russian asbes tos per short ton. average quotations for the year, as shown in Mineral and Metal Markets. All prices are c. i. f. New York. ASARCO ALV 0006331 S2 ASBESTOS Average price quotations per ton of foreign asbestos Year 1!1ZI .... 1921__ IMS 1930............................. 1931____ 1933.... . .. 1034 1935.............................................. 1936. ........................................... Rhodesiu . Russian no.: 2*0.2 11 Crude No. 1 Crude No. 2 Crude : Sbinele No. 3 stock !' i 325.00 3S3.33 301.17 1S7.50 186.67 210. CO 210.00 210.00 322.91 asn. oo 300.00 131.25 136.67 160.00 172.50 155.00 ; .................. i" 5210.00 227.50 213.51 212.50 192.50 5160.00 184.17 163.54 162.50 16150 167.50 220.00 186.00 * 1 550.00 113.54 125.00 125.00 12S.75 130.00 130.00 $55.00 55.00 5150 55.00 Beginning July 1935 a new grade of Russian asbestos designated Crude AA was quoted regularly at S450 a ton until February 1936. and at $475 a ton for the remainder of the year. MANUFACTURE OF ASBESTOS PRODUCTS A WIDESPREAD AND DIVERSIFIED INDUSTRY The fire resistance of asbestos combined with its fibrous, character adapt it admirably for the manufacture of flexible, heat-insulating products, packings, and gaskets for use in places where fabrics of animal or vegetable origin would be less enduring and would create fire hazards. The addition of asbestos to various fireproof building materials gives them strength and flexibility; and. furthermore, man ufacturers of many miscellaneous products find that asbestos, when used as an ingredient, imparts superior qualities. Thus many large industries have grown up in recent years for the manufacture of in numerable products of which asbestos is a major or an essential constituent. The Bureau of Mines deals primarily with.economic, technologic, and safety problems pertaining to raw materials of mineral origin; butj as the manufacture of asbestos products is very important in the United States, while the production of raw asbestos is a small indus try, more space than usual is given in this report to manufacturing processes and their resulting products. ASBESTOS-PRODUCTS PLANTS UNITED STATES The United States leads all countries in the manufacture of prod ucts of which asbestos is an essential or important constituent. The Bureau of the Census listed 238 establishments in the United States that made asbestos products in 1929, 208 in 1931. 187 in 1933, and 196 in 1935. The industry is centered chiefly in the North Atlantic States, notably in the Philadelphia (Pa.) and eastern New Jersey areas. Important factories are operated, also, in Cincinnati (Ohio), Chicago (331.), St. Louis (Mo.), and other midwestem cities; in the MANUFACTURE OF ASBES' Southern States: and on the Pacino coast: the domestic market: less than 5 percent, i The following table shows the quar p asbestos products manufactured in thv. .u as liven in the Biennial Census of Manufac as "other products" are very-numerous; s names sell more than 200 different articles, under the last four items in the table coi including wood, steel, copper, cork, and rn tos. which may form a very small proporti ASARCO ALV 0006332 s m of foreign atbestot Crude - Crude No. 1 No. 2 Crude No. 3 Shintrie stock 3210.00 227.50 213.54 212.60 212902..0500 3160.00 184.17 163.54 162.50 162.50 167.50 186.00 350.00 113.54 125.00 125.00 123.75 130.00 130.00 355.00 55.00 52.50 55.00 Russian asbestos designated 0 a ton until February 1936, he year. STOS TEODUCTS uizn hottstut .ed with its fibrous. character e of flexible, heat-insulating ? in places where fabrics of s enduring and would create to various fireproof building lity; and. furthermore, man tels find that asbestos, when qualities. Thus many large s. for +v>e manufacture of in is i ijor or an essential with economic, technologic, materials of mineral origin; ucts is very important in the iw asbestos is a small indusiiis report to manufacturing ruurrs .n the manufacture of prodimportant constituent. The iments in the United States 8 in 1931. 1ST in 1933. and liefly in the North Atlantic _) and eastern New Jersey . also, in Cincinnati (Ohio), sr midwestern cities; in the T ma^-facture of asbestos products 83 Southern States; and on the Pacific coast. . Most of the output enters the domestic market: less than 5 percent, in value, is exported. The following table shows the.quantity and value of tne principal asbestos products manufactured in the United States in recent years, as given in the Biennial Census of Manufactures. The articles listed as ``other products" are very-numerous; some manufacturing com panies sell more than 200 different articles. Many products included under the last four items in the table consist of various materials, including wood, steel, copper, cork, and rubber, in addition to asbes tos. which may form a very small proportion of the total. ASARCO ALV 0006333 Asbestos products vinnufac.lurcd in the. United Slides, HUO-Sd 84 ASBESTOS IS .. 'I I1 . 1> > =iils=ggls] SiSigii i :stggsiiBair=is aumcs* a-i gii - -- x '! s' il'ls'sWis'l' Is -r - ; si 1 ilsM mum 38 :! ss' ! -S i -mmu i nmm s' ia'^ss^s i ;; .i i umm mmlaigliEgsil si! iiiiii ,;i infjgmss ggSSS'g :l *S8 IS ----- - ta!* -- nrf- _ : .N-a-jf S5 I mms i 81 1 :5S ;8 j ! j s^=gs=; a g ISsSs :I : ! i 5 :2'*S' jsf : : : Ssiggiig 8g=fa=s a-"-' ?f S = I ISI5SS8 i 'll mmi-- mm - mmsag g nlaSgi 3 :I5S= II sSI i =' m ii Cttiri Pf- j sM si 5 mm il i i i : : 81 t nm : i i i;: s' a :a i ;;;; mum 5 1I I mmm is si's S= rsV ; -*=* SS=gg5S l =ggsi S iSsJIall : !s88^! s' :sSss~sf- ! MANTFACTCRE op asb Can ad., For many years Canada expo*" 4 raw asbesrtjs. bur lately it has di j nets industry. In 1934. 11 plants we ufactnre. Four of them, in the cente in Quebec, accounted for 40 percent were also six plants in Ontario and cipal products are brake-band linii packings, paper, and roofin':. The following table, compiled fr minion Bureau of Statistics, shows t recent years: Asbestos product.* plants CHEAT B The manufacture of asbestos pi in Great Britain. In 1929. 57 fat panies and the estimated value of the raw asbestos used. 44 percent c from the Union of South Afr,<-a. small amounts from Cyprus. The range of products is imk tl About one-fourth of the total outpi 1 GERM ,, In 1929, 32 factories in Gerrnai r which were devoted chiefly to spinr ; factories made corrugated sheetini bestos-cement products. The raw Russia, although substantial quai and Africa. As asbestos has no: quantity used annually in Germ; except ior fluctuation in stocks., n have increased from 7,580 tons in tons in 1934, and about 22.00U tons ACS In Austria, the original home o: factories were operated in 1929. cipal product of four factories. ASARCO ALV 0006334. I iSSISIsSSSIi is f-- SIs3 s Immu: i;; "T7" 3 :sf-*f=*3f ; { i iM: 1! 838855 J iSISs tiifw'tr. ... ill!S !3s :`g as' jias'rfmga'!.' M: : :l! Sisxgi ' iisgg 11 .smm ztnci ci- i jmris'emfef SS3i = !8S8i .siiiiM gMfUniirti : : iiaisggiiiiie^i 8 iSSlinig i I; IHMH! manufacture of asbestos products 85 CANADA For many years Canada exported almostits entire production of raw asbestos.'but lately it has developed an important asbestos-prod ucts industry. In 1934,11 plants were engaged in this line of man ufacture. i'our of them, in the center of the asbestos-mining district in Quebec, accounted for 46 percent of the total production. There were also six plants in Ontario and one in Nova Scotia. The prin cipal products are brake-band linings, boiler and pipe coverings, packings, paper, and roofing. The following table, compiled from data furnished by the Do minion Bureau of Statistics, shows the extent of the industry during recent years: Asbestos products plants in Canada. 1925-35 GREAT BRITAIN The manufacture or asbestos products is an important industry in Great Britain. In 1929. 5T factories were operated bv 35 com panies and the estimated value of their output was $23,163,000. Of the raw asbestos used. 44 percent came from Rhodesia. 2iy2 percent from the Union of South Africa. 21U, percent from Canada, and small amounts from Cyprus, the United States, Italv. and Russia. The range of products is much the same as in the United States. About one-fourth of the total output is exported. GER3CANT In 1929. 32 factories in Germany made asbestos products, IT of which were devoted chiefly to spinning, weaving, and braiding. Four factories made corrugated sheeting, pipe, roofing tile, and other as bestos-cement prodiuTts. The raw""asbestos is obtained chiefly from Russia, although substantial quantities are imported from Canada and Africa. As asbestos has not been produced in Germany, the quantity used annually in German asbestos-manufacturing plants, except for fluctuation in stocks, is identical with net imports, which have increased from 7.580 tons in 1932 to 12,600 tons in 1933. 20,000 tons in 1934, and about 22.000 tons in 1935. AUSTRIA In Austria, the original home of :;Eternit,J, nine asbestos-products factories were operated in 1929. Asbestos-cement tile was tlie prin cipal product of four factories. ASARCO ALV 0006335 86 ASBESTOS France In 1929. four factories in France produced asbestos-cement roofing tiles and similar products: nine plants were devoted chiefly to the manufacture of spun, woven, and braided products: four factories made high-pressure packings: and two factories made asbestos brake linings. iii.cit:jr Belgium has imported from Canada. Africa, and Russia between 1.200 and 3.000 metric tons of asbestos annually during recent years. Xine factories were in operation in 1929. but only fiye were reported in 1936. These firms consume oyer 90 percent of the imports of raw fiber. The principal products made are asbestos-cement shingles, tiles and pipes, and asbestos insulation. The output of millboard and woven products is small. Xo brake linings are made in the country. A large percentage of the imports of"fiber are of shingle grade. . ITALY In Italy, three large factories and numerous small ones manu factured principally asbestos-cement tiles and sheets in 1929. Thread, cards, cartons, textiles, and filter paper also are made in considera ble quantities. Two plants manufacture "Eternit'" products. The annual value of Italian asbestos products was estimated in 1932 at 25 million lire (about S2.061.775 on the basis of the 1935 rate of exchange). CZECHOSLOVAKIA In 1929. three factories in Czechoslovakia were devoted to asbestos spinning, weaving, and braiding; one made asbestos board; four, high-pressure packings; and several, asbestos-cement tile. Eight companies manufactured asbestos-cement roofing tiles in 1936. In that year the three largest companies concluded a cartel agreement whereby prices for domestic sales were increased substantially. The claim is made that the new price of 15 crowns (about 62 cents) a square meter gives the companies a small margin of profit. NETHERLANDS A plant for making "'Eternit" cement-asbestos gas and water con duits was built at Goor, Xetherlands. in 1936. FINLAND One factory established at Helsingfors, Finland, in 1923 manu factures "Eternit" products, packings, insulating materials, and fabrics. Both domestic and foreign asbestos are used. SCANDINAVIA Xorway imports 100. to 200 metric tons a year of asbestos from Finland. It is used chiefly for heat insulation. Two factories man ufacture asbestos packings, but their requirements of raw fiber are small. Similarly, few asbestos products are manufactured in MANUFACTURE OF ASB' Sweden. The country imports alxur nually. chiefly from Finland and Rm heat insulation. A. small ashest^-pi mark. In 1931. 1.040 metric u >f imported. .U'STKAJ There are quite a number of facte manufacture of asbestos products. Sydney, Brisbane, Melbourne, and P( are asbestos-cement sheet siding a pipe.. Sheet-metal roofing is used stantial substitution of asbestos-cem Asbestos production in Australia asbestos required is imported. T1 Canada are the chief sources of su figures show annual imports of a! 60,000. RCSS According to recent data, about of asbestos is used in domestic fact of asbestos products. Russia, thei factor in this industry. One very asbestos-cement products, fabrics. As a result of research conducted ai tute. several new products and pr< developed. The 1 aroslave Rubbei duction of molded asbestos brake other ct There are several asbestos fact* and Switzerland. Several ectabl' textiles, insulating: materia n* dently roofing is becoming a., im that country, because recently tl demand for shingle-stock fiber. FABRICATION OF , The manufacture of asbestos ' and complex processes. Only a ! erations is presented herein liecai raw materials. Fc Crude fiber delivered to the m:-, in a chaser mill, fiberized. and f: ing and air separation. I: is t cessive stages of manufacture i prepared by producers need not The processes involved in th< general those employed in spin ASARCO ALV 0006336 os rodi _asbestos-cement roofing its'\. .re devoted chiefly to the aided products: four factories o factories made asbestos brake i la. Africa, and Russia between s annually during recent years. '29. but only five were reported ) percent or the imports of raw are asbestos-cement shingles, on. The output of millboard rake linings are made in the imports of fiber are of shingle i numerous small ones manules and sheets in 1929. Thread, er also are made in considera-ure "Eternit" products. The cts was estimated in 1932 at 25 :e basis of the 1935 rate of iKIA vakia were devoted to asbestos e made asbestos board: four, . asbestos-cement tile. Eight ent footing tiles in 1936. 'In con eu"a carrel agreement : increased substantially. The 15 crowns (about 62 cents) a nail margin of profit. .ms !t-asbestos gas and water conin 1936. fors. Finland, in 1923 manu:s, insulating materials, and >estos are used. ia tons a year of asbestos from sulatioru Two factories manrequirements of raw fiber are ducts are manufactured in MANUFACTURE OF ASBESTOS PRODUCTS 87 Sweden. The country imports about 1,000 metric tons, of fiber an nually, chiefly from Finland and Russia. It is used principally for heat insulation. A small asbestos-products industry exists in Den mark. In 1934, 1,040 metric tons of unmanufactured asbestos were imported. AUSTRALIA There are quite a number of factories in Australia devoted to the manufacture of asbestos products. They are located chiefly in Sydney, Brisbane, Melbourne, and Perth, and their principal products are asbestos-cement sheet siding and roofing and asbestos-cement pipe. Sheet-metal roofing is used widely in Australia, and a sub stantial substitution of asbestos-cement sheets is anticipated. Asbestos production in Australia is small, hence most of the rawasbestos required is imported. The Union of South Africa and Canada are the chief sources of supply. The most recent available figures show annual imports of about 3,500 tons valued at about 60,000. RUSSIA' According to recent data, about two-thirds of the Russian output of asbestos is used in domestic factories devoted to the manufacture of asbestos products. Russia, therefore, is becoming an important factor in this industry. One very large factory, at Leningrad makes asbestos-cement products, fabrics, paper, and'insulating materials. As a result of research conducted at Leningrad by the Asbestos Insti tute. several new products and processes of manufacture have been developed. The Yaroslave Rubber Combinate has started mass pro duction of molded asbestos brake linings. OTHER COUNTRIES There are several asbestos factories in Poland. Hungary, Spain, and Switzerland. Several establishments in Japan make asbestos textiles, insulating'materials, and asbestos-cement products. Evi dently roofing is becoming an important branch of the industry in that country, because recently there has been an unusually large demand for shingle-stock fiber. FABRICATION OF ASBESTOS PRODUCTS The manufacture of asbestos products involves many diversified and complex processes. Only a brief summary of the principal op erations is presented herein because this report pertains primarily to raw materials. FABRICS Crude fiber delivered to the manufacturing plant usually is crushed in a chaser mill, fiberized. and freed from rock impurities by screen ing and air separation. It is then ready to enter the various suc cessive stages of manufacture into fabrics. Milled spinning fibers prepared by producers need not undergo this preliminary treatment. The processes involved in the manufacture of fabrics follow in general those employed in spinning and weaving cotton, wool, or ASARCO ALV 0006337 ss ASBESTOS .`ilk. Asbestos fibers differ from those of organic origin mainly in .thejtiinire of the surface. Wool fibers are covered with scaly bands known as imbrications, and cotron fibers are rough, twisted.'and ir regular. On the other hand, asbestos fibers have"no nodules, twists, or irregttlarities on the surface that- will enable one filter to cling to another. They tire more nearly akin to silk but are smoother and more rodlike.' This smooth, slippery condition creates such diffi culties; in spinning that the manufacture of a 100-percent asbestos yarn is slow and costiv: therefore a percentage of some ocher fiber, usually cotton, is added to act as a vehicle"to carry the asbestos through the manufacturing processes. The proportion of cotton added varies with the character of the asbestos and with the nature of the finished product. It rarely exceeds 20 percent, and with longlibered Canadian asbestos may be as low as 2 percent. Asbestos used in the manufacture of fabrics may consist- of a mix ture of varieties from different localities. The proportions depend upon the cost and quality of raw materials and the requirements of the finished product. Most manufacturers in America prefer Can adian fiber as a base, although many products now are made of African fiber alone. The blended fibers, together with the necessary addition of cotton, are mixed thoroughly with revolving beaters. Some manufacturers, however, introduce the cotton at a later stage. Carding is tlte next step in the process of manufacture. Carding rolls are covered with leather and fitted with sharp steel bristles. They comb the fibers parallel and remove short fibers, bits of rock, and* dust. After passing a succession of carding rolls the fiber emerges as a loose blanket, which may be turned 90 and passed through another carding machine. Tl'ie blanket then is separated into rovings, which are gathered in a roll on a Jack spool and spun into yarn, as in ordinary textile mills. Yarns are made in various sizes: a "5-cut" yarn measures about 500 yards to the pound and a "30-cut" yarn about 3.000 yards. When twisted exceptionally hard, if is known as asbestos thread and used in sewing gas mantles, asbestos theater curtains, and asbestos cloth ing. Tire spindles of single-ply yarn are transferred to_ twisting machines and twisted into two- or three-plv yarn, which is wound on spools. Asbestos cord and rope are ma'de by twisting together a greater number of strands. Where yarn is to be used for brake bands or packings, it usually is reinforced with fine copper, brass, or lead wire. Thus, for brake bands three strands of single-ply yarn and two strands of brass wire of gage nos. 0.006. 0.007. or 0.008 may be twisted together. For pack ings. a sinsrle lead wire or one to three strands of brass wire are twisted with two or three strands of asbestos varn. Products pre pared in this way are known as "'metallic yarns/' Yarns are woven into fabrics by well-known processes employed in cotton- or woolen-textile mills. 'Asbestos cloth is used for theater curtains, fireproof clothing, and many other textile products. Singleply asbestos yarn also is braided into tape. For electrical insulation it should contain not more than 7 percent carbon and not more than 14 percent cotton. Metallic yarn containing about 16 percent cotton is woven into strips for brake-band linings. Standard widths range from 1 to 6 inches and standard thicknesses from one-eighth to sv: manufacture of asbes three-eighths inch. They are nrocesse. grertients. The manufacture of b is the most important branch of gj indicated in the table on past- S-i. strii 1920 totaled more than 20.000 miles Asbestos packings are mack- in vari. twisted or braided into valve-sunn pacl be compressed into rings, or amtos e or other desired forms. Thev mav be rubber compounds, oil. or flake Manlr some packings, e1 shingles and l Roofing shingles are made of a mixt cent Portland cement and 1.' nevcent s manufactured by the so-calleil "dry ] and coloring agent are mixed dry'in with paddles. The mixture is spread belt and sprayed with wafer a: ISO1 required thickness, and a rotary cutti shingles. The shingles are piled in st and squeezed in a hydraulic press at r square inch, after which they are cut nailing. Shingles are also made by tite wet ] mg paragraph: Asbestos lumber and shingios mav "Eternit" process first used in Austrh and coloring matter are mixed with fated thoroughly with a beater, and p builds up the sheets in successive lai ness. Portland cement thus mixed \ does not lose its capability of s-"':ng the water is removed. For s le made. Lumber consists of thi-mer : sheets are made by crimping tint sh I used also for making cemem-asbesto I tube-shaped articles is more com ' equipment. i * Asbestos lumber is also made by t kf ouslv, but more time is needed for c j required for the thin sheets used for r.vPEr. and m Asbestos of paper-stock grade is i water to make a thin slurry, which | drums covered with slats. Starch, 1 derived partly from the overflow sqi , stage, are adcled to the slurry. Tlj machine similar to that used in the i j or wood pulp. All particles of stoi j inated in a sand-catching and knot; of paper pass between rollers to rer ASARCO ALV 0006338 of organic origin mainly in arer'__. ?red with scaly bands rs a. .ough, twisted, and iriliers have no nodules, twists, II enable one fiber to cling to o silk but are smoother and condition creates such diffiire of a 100-percent asbestos rcentage of some other fiber, chicle to carry the asbestos The proportion of cotton asbestos and with the nature ;ls 20 percent, and with long er as 2 percent, abries may consist of a mixis. The proportions depend ials and the requirements of .ers in America prefer Canproducts now are made of . together with the necessary hlv with revolving beaters. i tlie cotton at a later stage. s of manufacture. Carding d with sharp steel bristles, ve short fibers, bits of rock, of carding rolls the fiber ' be turned 90 and passed i blanket then is separated il on a Jack spool and spun o-cut" yarn measures about ;-n ab*"U 3,000 yards. When as a :os thread and used urtau.j. and asbestos clothire transferred to twisting -ply yam, which is wound ma*de by twisting together .nds or packings, it usually lead wire. Thus, for brake d two strands of brass wire wisted together. For pack- strands of brass wire are >estos varu. Products preyarns."' "known processes employed os cloth is used for theater ar textile products. Single. For electrical insulation carbon and not more than ng about 16 percent cotton rs. Standard widths range nesses from one-eighth to { MANUFACTURE OF ASBESTOS PRODUCTS 89 three-eighths inch. They are processed with rubber and other in gredients. The manufacture of brake-band linings for automobiles is the most important branch of the asbestos-products industry. As indicated in the table on page 84-, strips woven for this purpose in 1929 totaled more than 20,000 miles. Asbestos packings are made in various ways. The yarn may be twisted or braided into valve-stem packings, the braided forms may be compressed into rings, or asbestos doth may be cut into gaskets or other desired forms. They may be coated or impregnated with rubber compounds, oil, or flake graphite. Metallic yarn is used in some packings. SHINGLES AND LUMBER Roofing shingles are made of a mixture of approximately 75 per cent Portland cement and 15 percent shingle-grade asbestos. When manufactured by the so-callea "dry process", the cement, asbestos, and coloring agent are mixed dry in a cylindrical mixer provided with paddles. The mixture is spread evenly on an 18-inch conveyor belt and sprayed with water at 180 F. Rollers compress it. to the required tnidtness. and a rotary cutter separates it into individual shingles. The shingles are piled in stacks separated bv steel pallets and squeezed in a hydraulic press at a pressure of 20.000 pounds per square inch, after which they are cured, trimmed, and punched for nailing. Shingles are also made by the wet process described in the follow ing paragraph: Asbestos lumber and shingles may be made by the laminated or "Eternit" process first used in Austria. Cement, shingle-grade fiber, and coloring matter are mixed with a large quantity of water, agi tated thoroughly with a beater, and pumped to a paper machine that builds up the sheets in successive laminations to the desired thick ness. Portland cement thus mixed with a large quantity of water does not lose its capability of setting at a later stage when most of the water is removed. For shingle manufacturer thin sheets are made. Lumber consists of thicker and larger sheets. Corrugated sheets are made by crimping flat sheets. The laminated process is used also for making cement-asbestos pipes, but the building up of 1 tube-shaped articled is more complicated and requires special equipment. Asbestos lumber is also made by the dry process described previ ously, but more time is needed for compression and curing than, is required for the thin sheets used for roofing. PAPER AND MILLBOARD Asbestos of paper-stock grade is .mixed with a large amount of water to make a thin slurry, which is agitated thoroughly by 5-foot drums covered with slats. Starch, flour^ or size and sodium silicate, derived partlv from the overflow squeezed out of the paper at a later stage, are added to the slurry. This is then conveyed to a paper machine similar to that used in the manufacture of paper from rags or wood pulp. All particles of stone or other impurities are elim inated in a sand-catching and knot-removing machine. The sheets of paper pass between rollers to remove most of the water and are '! ASARCO ALV 0006339 90 ASBESTOS dried in hot cylinders and wound in rolls. If a two-ply paper is de- .. sired, one side of a sheet is coated lightly with sodium silicate, and the two sheets are run together over several hot rolls. Crimped paper is made by passing it over corrugated rolls. In the manu facture of air-cell pipe covering, the tips of the corrugations are coated with sodium silicate, and a flat sheet is added. When this process is repeated, a two-ply. three-ply, or thicker air-cell covering jnav be made. Millboard is generally classed with paper because it- is manufac tured by the same general process. It is simply a thick paper: it bears the same relation to asbestos paper that cardboard bears to wrapping paper. The hoard usually is built up on rectangular screens rather than on drums. _ The manufacture of millboard gaskets is important. The high speeds, temperatures, and pressures attained in modern automobiles and other machinery demand very exacting qualities in the millboard used. It must have uniform density and high strength, and varia tions in thickness in any part of the sheet must not exceed two one- thousandths of an inch. COMPOUNDED PACKINGS Certain types of asbestos packing are made by mixing clean, wellopened fiber with fillers, such as clay, barite, magnesia, iron oxide, graphite, or cellulose, and binding materials, such as gums, resins, lac, or rubber dissolved in benzine. High-quality sheets contain about two parts asbestos to one part filler. The mixture is molded into sheets of the desired thickness. Several sheets may be glued together and reinforced with copper or lead foil. MAGNESIA INSULATION For the so-called "85-percent-magnesia ' pipe covering a good grade of asbestos--chrysotile, blue asbestos, or amosite--ranging from 0-6-6-4 to 0-5-S-3 is used. Approximately 15 percent of fiber is mixed with 85 percent of basic magnesium carbonate derived from dolomite, magnesite, or bitterns at salt works. These ingredients are mixed thoroughly with water and filter-pressed into cakes, which are dried for 3 clays in steam-heated kilns. The blocks are then trimmed, cut in lengths, and bored to form hollow cylinders: these are sawed lengthwise, and the half-cylinder sections are rolled in pairs in glued canvas jackets. For ordinary use the walls have a maximum thickness of about 2l/n inches. ASBESTOS CEMENT A covering used widely for boiler insulation consists of short-fiber asbestos antfa cementing material such as plastic clay. The ingredi ents are mixed with water to form a paste, which is* applied with a troweL COLD-MOLDED ARTICLES Increasing quantities of short-fiber asbestos are used in the manu facture of electrical fittings and household appliances. Mixtures of asbestos, gilsonite, cement, and oil are ground together and com ( f t j ( i t h f ( )1 ' pressed in molds: these are baked in oi Gilsonite imparts a brown color; ` t omitted. noncorkosive t. Amphibole ashestos. which in general than chrysotile. is washed, thormiehlv pared for use in Gooch crucibles or for employ strong acids and alkalies. SELECTED BIBLIO Allen, U. A., and Butler. G. M. Asbestos, t Asbestos. A magazine devoted to the ashes July 1019, 16th Floor, Enquirer Bldg., P Becker & Haag. Asbestos. Book publisher 8S pp. Berlinract, L. Ashestos Mining Reviving Press, vol. 101, 1926, pp. 164-1G7. Bowles, Oliver. Asbestos. Chapter In I Edited by J. E. Spurr, 1920. pp. KSS--101. Bureau of Foreign and Domestic Comme Trade Iuf. Bull. 442, 1026. 22 pp. --------- Asbestos; World Production and 10 pp. Cirkel Frttz. Chrysotile-Asbesfos. Its Oo Uses. 2d ed. Canada Dept. Mines. Mil Cooke. H. C. Asbestos Deposits of Thett vol. 31, no. 4. 1936. pp. 333-376. --------- The Composition of Asbestos and Quebec. Trans. Roy. Soc, Canada, thir Coclson. A. L. Asbestos in the Ceded D With Notes on Its Occurrence its Othe vey India, vol. 64, pt. 2, 1934. 26C pp. Diller. J. S. The Types and Modes of Or States. Jour. Canadian Min. In: >1 Dresser. John A. Asbestos in Souths. _ Q vol. 50, 1915. --------- The Ashestos Deposits of the Ea Geol., vol. 4, no. 2. 1909, pp. 132-140. Fisher. Norman R. The Quehec Ashestt vol. 44. 1923, pp. 649-633. Gamble. William B. Asbestos. A list of Turk Public Library, 1929, 72 pp. Hall A. L. Asbestos in the Union of So Geol. Survey Mem. 12, 2d ed.. 1930. 32- --------- On the Asbestos Occurrences Nen District. Trans. Geol. Soc. South Ai Hopeins, Oliver B. Asbestos Deposits Eng., vol. 50, 1915. pp. 964-973. -------- Asbestos, Talc, and Soapstone Di Georgia Bull. 29, 1914, 319 pp. Imperial Mineral Resources Bureau. London, 1921, 34 pp. --------- The Mineral Industry of the Brit Asbestos, Statistics (1919-21). Londo: 1925, 23 pp. Imperial Institute. The Mineral Indust eign Countries. Statistical Summary, <1 ASARCO ALV 0006340 ills. If a two-ply paper is deitly ;th sodium silicate, and se 1 hot rolls. Crimped rug'ated 'rolls. In the manutips of the corrugations are t sheet is added. When this v, or thicker air-cell covering paper because it is manufac; is simply a thick paper; it .per that cardboard bears to is built up on rectangular e_ts is important. The high lined in modern automobiles ing qualities in the millboard ad high strength, and varia nt must not exceed two one- KXXGS made by mixing clean, wellbarite, magnesia, iron oxide, erials, such as gums, resins, High-quality sheets contain ler. The mixture is molded :everal sheets may be glued lead foil. .xxoir pip<* covering a good grade or osite--ranging from ateij io percent of fiber is um carbonate derived from -orks. These ingredients are iressed into cakes, which are The blocks are then trimmed, r cylinders? these are sawed ; are rolled in pairs in glued ills have a maximum thick- H 1 V rr lation consists of short-fiber 5 plastic clay. The ingredite, which is applied with a :les estos are used in the manu!d appliances. Mixtures of ground together and com SELECTED BIBLIOGRAPHY 91 pressed in molds; these are baked in ovens, polished, and lacquered. Gilsonite imparts a brown color; if gray is desired the gilsonite is omitted. XOXCORROSIVE FILTERS Amphibole asbestos, which in general is more resistant to chemicals than chrysotile. is washed, thoroughly fiberized, and otherwise pre pared for use in Gooch crucibles or for other filtering processes that employ strong acids and alkalies. SELECTED BEBLIOGBAPHY. Allen, 31. A., and Butleb, G. 31. Asbestos. Unir. Arizona Bull. 113,1921. 31 pp. Asbestos. A magazine devoted to the asbestos trade, published monthly since July 1919, 16th Floor, Euqulrer Bldg., Philadelphia, Pa. Beckeb Sc Haag-. Asbestos. Book published by Becker Sc Haag, Berlin, 1928, 88 pp. Berlinbaut, L. Ashestos llining Reviving In Russia. Eng. and 3IIn. Jour. Press, vol. 121, 1926, pp. 164-167. Bowles, Olivek. Asbestos. Chapter In Political and Commercial Geology. Edited by J. E. Spurr, 1920. pp. 3S8-401. Bureau of Foreign and Domestic Commerce. Asbestos, Source and Trade. Trade Inf. Bull. 442, 1926, 22 pp. ---------- Asbestos; World Production and Trade. Trade Inf. Bull. 20, 1922, 10 pp. Cirkel. Fritz. Chrysotile-Asbestos. Its Occurrence. Exploitation. Mining, and Uses. 2d ed. Canada Dept. 3Iines, 3Iines Branch, 1910, 316 pp. Cooke, H. C. Asbestos Deposits of Thetford District, Quebec. Ecou. Geol., vol. 31, no. 4, 1936, pp. 353-376. ---------- The Composition of Ashestos and Other Fibers of Thetford District, Quebec. Trans. Roy. Soc. Canada, third ser., vol. 29, sec. 4, 1935, pp. 7-19. Coclson. A. L. Ashestos in the Ceded Districts of the Madras Presidency: With Notes on Its Occurrence in Other Parts of India. Mem., Geol. Sur vey India, vol. 64, pt. 2,1934. 266 pp. Diuler. J. S. The Types and 3Iodes of Occurrence of Asbestos in the United States. Jour. Canadian Min- Inst., vol. 14, 1911. Dresser, John A. Asbestos in Southern Quebec. Trans. Am. Inst Min. Eng., vol. 50, 1915. ---------- The Ashestos Deposits of the Eastern Townships of Quebec. Econ. Geol., vol. 4, no. 2. 1909, pp. 132-140. Fisher, Norman R. The Quebec Asbestos Industry. Canadian 3Iin. Jour., vol. 44, 1923, pp. 649-633. Gamble. William B. Ashestos. A list of references to material in the New York Public Library, 1929, 72 pp. Hall. A. L. Asbestos In the Union of South Africa. Union of South Africa Geol. Survey Mem. 12, 2d ed.. 1930, 324 pp. ----------On the Asbestos Occurrences Near Kaapsche Hoop in the Barbeton District. Trans. Geol. Soc. South Africa, vol. 24, 1921, pp. 16S-181. Hopkins, Oliver B. Asbestos Deposits of Georgia. Trans. Am. Inst. 3Iiu. Eng., vol. 50, 1915, pp. 964-973. ---------- Asbestos, Talc, and Soapstone Deposits of Georgia. Geol. -Surrey of Georgia Bull. 29, 1914. 319 pp. Imperial Mineral Resources Bureau. Asbestos, War Period (1913-19). London, 1921, 34 pp. ----------The 3Iinera! Industry of the British Empire' and Foreign Countries. Asbestos, Statistics (1919-211. London, 1924, 16 pp.; Statistics (1920-22). 1923, 23 pp. Imperial Institute. The Mineral Industry of the British Empire and For eign Countries. Statistical Summary, 1933-35. London. 433 pp. ASARCO ALV 0006341 92 asbestos Jones. Robert H. A.-liestoj. In- Projimios. Occurrence, and Uses. London. _ ._..1S90, 230 i>p. Keep. F. E. Geology of the niromitr- and Asbestos Deposits of the Cmnikive Range. Lmuagumli and Mazoe Districts. Southern Rhodesia Geol. Survey Bull. I'l. J!i3<i, 5do pp. ---------- Tin- fhrysnrilo Asbestos Deposits of Sliahani. S. Rhodesia. South Africitu Min. uml Eng. Jour.. Apr. 12. 1930. pp. 10S-170. ---------- Tlie Shuhani Asliestos Deposits. South African Min. and Eng. Jour.. Mar. 3. 192S, pp. 5-0. KfPTERnuncEr.. IV. Minina Atnosite Asliestos in the rietersburg District. South Africa. Eug. and Min. Jour., v<l. 130. 1030, pp. 571-571. Marcuse. B. Asliestos (chapter in Marketing of Metals and Minerals, edited 1 iy J. E. Spurr and F. E. Wormser). 1925, pp. 235-242. ---------- I'ierre 5 Cotou. Canadian Geog. Jour., vol. 1, no. 6. 1930. pp. 497-522. Mineral Industry (Tliel. Edited by G. A. Rousch. A series of volumes pub lished annually from 1S92, statistics, technology, and trade. Chapter on asbestos tacit year. Mineral Production of Canada. Prepared by Dominion Bureau of Statistics. Published annually. Mineral Resources of the United States. Pt. II. Xonmetals. Statistical and economic compilation, published eacli year front 1924 to 1931 by the C. S. Bureau of Mines: before 1924 by the U. S. Geol. Survey: since 1931 published as Minerals Tearhook; chapter on asbestos each year. Minerals Tearrook. Statistical and economic compilation, published eacli year since 1931 by the U. S. Bureau of Mines: before 1932 published as Mineral Resources of the United States; chapter oil asbestos each year. Quebec Bureau of Mines, annual Reports. Mining operations and statistics. Ross. J. G. Chrysotile Asbestos in Canada. Canadian Dept. Mines, Mines Branch, no. 707, 1931, 146 pp. Ilu Keyser. Walter A. Asbestos Mining in Quebec. Eng. and Min. Jour.. vol. 133. 1932. pp. 17-22. ---------- Asbestos Mining and Milling in Quebec. Eng. and Min. Jour. Press. vol. 113, 1922. pp. 617-4525. 670-677. ---------- Chrysotile Asbestos in the Bajenova District, C. S. S. R. Eng. and Min. Jour., vol. 134, 1933, pp. 335-339. ---------- Mining Asbestos in U. S. S. B. Eng. and Min. Jour., vol. 134. 1933. pp. 31 *>--3S1. ---------- Ashestos Milling in the Urals. Eng. and Min. Jour., vol. 134. 1933. pp. 415-419. Spence. Hugh S. Asbestos Industry. Trans. Canadian Inst. Min. and Met.. vol. 2S, 1925, pp. 94-9$. Taber. Stephen. The Genesis of Asbestos and Asbestiform Minerals. Am. Inst. Min. Eng. Buil. 119, November 1916, pp. 1973-199S. (Includes dis cussion.) U. S. Tariff Commission. Ashestos. Tariff Inf, Surveys, rev. ed,, 1921, 56 pp. -------Report to President. Russian Asbestos, Rept. 67, 2d ser., 1933, 11 pp. o 15 u i i After this publication has served your pi no further need for it, please return it tc The use of this mailing label to do so u and no postage stamps will 1 UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU of mines OFFICIAL BUSINESS RETURN PENALTY LABEL Thii libel can be uicd only for returning obefecchiaanl pceudb.lication*. The aUtlrea* must not BUREAU ( WA 4 ASARCO ALV 0006342 Occurrence, and Cses, London. jC?** a -Deposits of the Cmvukwe Soutnern Rhodesia Geol. Survey ' ShnhanL S. Rhodesia. South lip. lOir-170. i African Min. and Eng. Jour., ~ in the Tietersburg District. SO, 1030, pp. 571-574. of Metals and Minerals, edited pp. 235-242. .. voi. 1. no. 6, 1030, pp. 497-322. usch. A series of volumes pubnology, and trade. Chapter on Dominion Bureau of Statistics. Pt. II. Kosmctals. Statistical year from V.124 to 1931 by the the Tj. S. Geol. Survey; since pter ou asbestos each year, ic compilation, published each lines; before 1032 published as chapter on asbestos each year. `lining operations and statistics. Canadian Dept. Mines, Mines Quebec. Eng. and Min. Jour., x.. Eng. and Min. Jour. Press, District, C. S. S. R. Eng. and arrt_Min. Jour., voL 134. 1033, a._.jitlin. Jour., vol. 134, 1033, Canadian Inst. Min. and Met, nd Asbestiform Minerals. Am. . pp. 1973-199S. (Includes dis- .f. Surreys, rev. ed., 1921, 56 pp. -ept 67, 2d ser., 1933, 11 pp. tt } ( * i1 | Tj J After this publication ha* served your purpose and if you hare no further need for it, please return it to the Bureau of Mine*. The u*e of this mailing label to do so will be official business, and no postage stamps will be required UNITED STATES DEPARTMENT OF THE INTERIOR BUREAU OF MINES PENALTY FOR PRIVATE USE TO AVOID PAYMENT OF POSTAGE. WOO OFFICIAL BUSINESS RETURN PENALTY LABEL Thi label can be used onlyfor returning official pubZicacioaa. 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