Document e7jb1ezX0XomXvr5jqxkd3g4p

*-'f"r-t tt htts Jahimny 1933 Department of the Interior UNITED STATES BUREAU OF MINES W.John Finch, Oinccton INFORMATION CIRCULAR ASBESTOS - GENERAL INFORMATION 8Y O .1 vtm So(Lt* 001560 -'() ;) u T-t--i | -f 0 J~ I.C. 6817 January, 1035 iiO'CKv.Tiy.: cip.auji or ?:s i::r:3i3n - hurlo; o? ui;ss asbestos - cii-mAi i;:?c3:iatio:;1/ By Olivor Bodes?!/ Definition................................................ . . ......................... ............................. , , 2 Varieties............................................................................................................... .... . , 2 Sources of supply end turn used In ancient tines ,....................... . . 2 Origin ................................................................................................................ ..... 4 Uode of occurrence .......................... .... ..... .......... 4 Physical properties t... 5 Outstanding characteristics .................................................... ........ 5 fibrous character................................................... .5 Fineness of fiber .......................... ........... ...................... . 5 Color end luater............................................\ ........................... .... 6 Heat resistance ...................... ;................................................................ 6 Heat conductivity ............. ...................... ...... 6 Acid reslst&rxs........................ 6 Dlectrical resistance ....................... Chenicnl composition . . .................. ...... ... ....... 7 Uses ......................... ...................... 7 liir.ing methods..................... 8 Arizona .............................. 6 Vermont..................... 9 Georgia sud Duylaud ........................................................... 9 Quebec ....................................... ..................... ` .......................... 9 Rhodesia .............................................................................. , .......................... .... 10 Union of South Africa .................. .................. 10 r.ussla . .................................. 11 Cyprus.............................. 11 Usrld production.................................................... .....................'......................... 12 Uorld consumption .. ...................... .................. 14 Political and cnvcorclal control ............................................................................. 18 Political control...................... ",...............................................................................18 Corr-.ercial control .......................................................................................................18 Foreign trade .......... ......................................................................... 17 Imports ...................... . . ...... ...................... .......... 17 Imports....................................................... 21 u ?r.o Bureau of :?lncs Vill u.lco-: rtprintir,; of this pno.T, provided the folloi. ing foot ictc Rcimorlodgu-nl is ucc.: "-.'.or .r.tcd from U. S. 3urcau of fines Infor atlon Circular 6?.rV Thic paper is the cocond of a r^rict of repo`is or. the .-.r'jcfio" I'iustr/. T-o flrrt rcoort, I.C, 67?0, is entitled *M :ocVor - Dov.stic -rtf ?o;-sl.;n Droorlts.* l! e-A;ir.r 'cu.lJinj mi: ials scctlcn, *J. 5. 3v 0045'6i n <) i ; i i 8 j 7 :.C. C617 XEFi:;ino3 "Asbestos* 1* .iot the name of a distinct mineral species but 1 rather a coar.icrcicl tern,applied to fibrous varieties of several minerals. Tho origin and significance of names applied to asbestos by early writers are discussed in the section devoted to sources of sinply and terms employed in ancient times. VASIT.'IES The moot useful varioty of asbestos is chrysotile, a fibrous serpentine the composition of which is expressed Vy the formula Chrysotile is characterized by a strength and fleeibility that perait tne use of tho longer fibers for spinning, Eie bulk of the narld production of both long nnd short fibers ie of tale variety. ........................................... Other varieties of asbestoo belon,: -to the asphibole group of minerals. Antb.ophyliito,- havlvg the composition 'Pe,Ug)Si03, is the type most abundant in the United State:!. Usually it lr b> ittle and of low tensile strength and is more resistant to the action of acb.s and heat turn chrysotile. It is used for r.oncplnnihg purposes, Anoslts, a peculiar variety of iron-rich ar.tr.ophyllite occurring in Africa, it notable for the length of its fiber. The best-grade material lo used for ep.nr.ing. Plbrorun trcmolite, Ca^g3(Si03)4, rxtinolite, CoOl^oJjfSiOjj)^,' and hornblende, a complex cili- cate similar in composition to actlnollte,- generally are regarded as the minerals to which the term "asbestos" was originally applied. Except for Italian trenolite they have llttlo coarsercial value, itountaln loather and mountain cork are vixietios of omphibolr consisting of flexible sheet* of interlaced fibers. Uount&ln wood Is a compact fibrous mass of annhibole resembling dry rood. The last three varieties are-mineral curiosities and have no commercial \alue, Crocidolite, also called "blue asbestos", having the composition I!ajT<{SiOjigVeSiOj, is an unusual amohibole occurring in coa- ir.ercial quantities chiefly in Africa. It is used for both spinning and no.-.spinning purposei . `........................................... S0USCS3 0? S'J??LY AID TZSIS EMPLOYED IZT XL ZZ212 TIGS The word "asbestos", evidently first appllod by Pliny to the fibrous mineral non kr.om by that name, ras employed erroneously, for in both ancient and modorn Greek it refers to ruicl:llr.e, The Croe.n oerd "asbestos" means "ir.extinguis2u.ble* or "unquencl-xolo" - : or As conveying quite the opposite meaning fr^m "incombustible", a ciutructeristlc feature of nsbesios. Possibly Pliny had n. nind Plutarch*s reference to the "perpetual* asbestes la-rp nicks used by .he Tettal Virgin*. "blti.es cr.iar.tos", iho original tern used by the Or :ect for asbestos, t a roc'.: ur.itsi.-xd, ur.tair.ted, or urulefiled and doubtless referred to the clean ring of asbestos clotii by tkrocing it in the fire. Another co~::i name applied to r.rbetos .-a: "Ecrystios lithos" became --c-ll-'.-orn source cf flexible miner:.! . iber was near Tx.rjstos, southern -2- 004562 0 rt..: v--- u a u-fj-t-ii i r-r^ra I.C. 6ei7 Euboea, Greece. Ztrly lr. the first century Strabo referred to stone from "thli locality that too carded and rover. into'handkerchiefs. Solinus and Pluterch also section a fibrous nlneral fron this place. These ancient writers evidently laiew little of the deposits, but as tno exposure* of ser pentine occur east of Xarystos the fiber probably ins chrysotiloJU Paucanius, rho livt.d in the iecond century A.3., refers to lneonbustible "Knrpasian flax." Soae writers think this tera iudicatos that the source of the fiber ras Larwasos, northeastern Cyprus, but no asbestos-hearing rock is known in that vicinity. Evans points out tiiat the word "jlarpatos" neons cctlor" and tiiat probably it ras applied to the mineral because of its adaptability to textile use .5/ Cyprus, 'however, wns a well-known source of supply of asbestos iii ancient tines. Although it is difficult to detemlne fron early references the exact location of the deposit, probably it ras southeast of Uour.t Troodos in a village Jyioim as "Anianto", the identity of nhlch is lost. Turing recent years chrysotilo acoestos has been produced in considerable quantities near a to.m nc'i Known an "Aniandos." This is probably the site of nnclent Asiauto, for it is situated near liour.t Troodoe 10 niles froa the seaport Llaasol. .. ' The asbj.-tco used by tho Rooms doul .less ras n long-fiberod variety ldentifiod as trenollte and occurring in :northern Italy. The use ef Italian fibtr presumably led to the claim ridely isade in literature that the original "anientoe" consisted cf fibrous anphibole (trenollte, actinollto, ar horn blende). A recent pei sonal corrr.unication from the chief mineral Inspector in Rone, however, caste cone 'doubt ae to whether Italian fiber used by the ancients ras trenollto. A significant sxcerpt fron this cossauaication reads a* follorsi Tor a long tine it ms believed that tho Italian "mior.ti* rero all the tranollto typo bccauso the first examinations of the natorial rere based on sennits of trenollte. It r*s only in recent yenfs that, after further studlss, the producers recognixod that thtlr products rere for the nost p.irt c.irysctile with a long, flexible fiber. . U&rco Polo refers to "relentos* cloth shorn to l*lm during **1* travels through Siberia. The I'sst-lmswn asbestos if Siberia is chrysottlc occurring at tii-ulslnck near the Mongolian border, Thus it appears that outs ids of Italy all tho l:uom. astertoo deposits cert sources of ehrysoillt end not cmphi'oole. Turthcr ovidence that tho tens "a.sintos" at used by tho ancients ray have app'.iod to ciirysotlie as well as to arnhlboJe is found in the uses of the material, With th* exception of twisted fiber used for Inc* ricks prac tically all the early leftrsr.cos are to textile ure. Acber.tos was rover, into hmdkci chief*, tabled'the, winding shoots, anl tlnllar fabrics. Uost i/" "jV-vT?., ~rf~IdentTtyVf"tho Aulu .tos or rystiar. Store <"f the Ai.cier.ts nth C.ry lOtllcs !li:.eralowical i^g. (London), vol. 11, liay ICOu, pn. 10-43. if Evans, John Tork cited, p. 1<3. 2;? - 3 - 004563 U ;{ 9 i.c. cb:7 varieties of ampkibole arbor too are weal: and brittle and cannot be npun or woven. The principal sxccwt ior.s, aside from the trc.-.olite of lirly, are t!ie crocldollte ar.d amasite of Couth Africa - varieties xisnorn until cccrpr.ratively recer.t year?. Chrysotlle, on the ether hand, is strong, flexible, and silky ar.d well ciaptsd for textiles, Judging from the probable sources of supnly it scent reasonable to co.iclodo that it was CJspl.oyed in ancient times in the canufaciuru of incombustible fabrics, okiciw Asbestos originates Tor the most part from rocks consisting largely of olivine, i urh ns peridotlio or dur.ite, or frem pyroxonite, Most citrysotile depc-nits rrc..dt from nlte-atlor. of olivine tk sc.rper.tine, with cub sequent prismatic crystallisation provldli,g the fibrous struutue, The alteration is effected by intense me".amorpclsm. Contact as well as regional metamorphiom evidently plays an :.wportant part ia tie process because in various regions, notably the Canadian ar.d Bixdssian Holds, intrusive rocks are associated with the deposits and doubtless definitely influenced their de velopment, Prismatic crystallization occurs in fractures. As recrystalliza tion evidently occurs along the vein nails, the veins nay be regarded as of the replacement rather than the fissure type. Carysotile occurs in two forms - cross fiber and slip fiber. The ferner is the characteristic occurrence In all replacement reins, the fibers cross ing the veins at right angles to the calls. -Jence the fiber length is governed in general by the width of the vein. Slip fioer, on the ether hand, parallels the vein wall and usually thews the effects of pressure ard novenent along a fault plane. The chrysolite occurring in sedimentary rocks in Arizona and in tho Carolina district of the Transvaal originated, in a quite different way. The fiber in these localit.es is regarded as a product of alteration of mag nesian limestone cetamcrpltnoed by diabase intrusions. It occur:* in cross fiber veins. Under rote conditions peridotitoa and pyronenitco are nltrrcd to fibrous nrnhibcles, of which the nest common is r.nthoohyllito. In some places it c:r.^-s as slip fiber in shear zones, tut .-.ore commonly the altered rocl: take: top form of pockets or ler.i** co.iclstijr almost entirely of irregularly r-rrc-vcd bundles of fiber. Tho rock is called "aciphlbolite", and the nsbcctos 1* of toe cast-fiber type. T.ie crocidollts ar.d smite of South Africa originated from rocks ruitc distinct from peridoilt* cr pyror.er.lte, Taey were derived frum sediments rich ir. iron ur.d stiles, la.own as "banded ironstones*. Prismatic crystalli zation In cross-fiber veins probably oao assisted to tome cutout by contact notamorphlam. U0D2 C? OCCtV-HZlCZ ~r:w the dlscucslon of origin It is evld-nt that thcro are three tipi** of no: cotes d''no sits - crocr. fiber, clip fiber, -rilrnsr. fiber. Cross-fiber <*':s'.os consists of lr.r.u.nu*nble strand* 'ztr a'l p nt. -of.- veins from rail to '~P7 - f. - <J045'64 l.C. I-S17 rail, except whure interruntcd by longitudln \1 sewr.s. Uot cortr.srcial de posit t of ciu-ytotile, axosita, and crocldoll ;o.are of thla type, but anthophylllti: rarely, If over, occur* ir. croes-fi->er vein*. In sl'ip-flbsr de posit* the .strands r.ore or let* parallel the vein n.mlls. They frequently shon sl.chensldcd surfaces 'oecr.ue* thoy occupy shear cones nhoro tho rock hr.* been subjected to movement and pressure. Slip fiber is common in the chry6ot:le deposits near Edi:i, Yt., and predominates In the onthophyllite deposits at Fylesvillc, I'.d., ond uear Bedford and Eccky tiount, Va. In nass-fiber deposits there is no definito orientation of fibers. Almost ti'.e entire mass of the rock is conpossd of bundles of fibers or needles that scxctir.es show a radiating structuro. This type of occarrcr.ce is confined almost exclusively to tho anthopnyllitc variety and is wellexemplified by deposits i.t Sail iiountain, G*., and Jkirinh, Idaho. ' FnYSICAL PROPZSriSS Outstandln.- Chr.ractc r? :tlcsThe most characteristic properties of asbestos - those that give it commercial value - art fibrous structure ar.d fire, resistance. The lowest and strongest fibers licve qualities possessed by no other rVurral, in that they may be spin into yarn or thread, roven into cloth, or felted into sheets and pachit gs in almost tho tone nny at animal tr.i vegetable fibers, but unlike cot1, on or wool they consist of in combustible natter. Fibrous CharacterAlthough all asbes'os is fibrous, the quality of the fiber in the various types ar.d ir. different deposits is quite diverto. Chrysotile, cmor.lto, ar.d crrcic'olitc normally posses high tensile strength, flexibility, and elasticity, but these qualities vary greatly in Material free different localities. Chrysotlle orcar.ior.ally is harsh and somewhat brittle, Crocldollts is said to be stronger than chrysotilc. *Tae fibers of axosite are exceptioru-lly long. Ar.thophyllite l* brittlo and of low tensile strength, although the fiber from sons deposits has con siderable strength and toughness. This type usually is more flexible t'nan fibrous tre.aslite or actlnolltc, Trenolite is generally too weak end brittle for textile use; Italian trenolite, however, is said to be of spinning grade. Length of fiber is irwortant in asbestor. strong and flexible enough fdr\spinning, ar.d weaving. The fiber is graded rn ihe basis of lengtn, and rust crisis of identical quality .may rango in price from $20 to tSCO a ton, according to grado, Flr.er.csr of Fiber.- Fineness of fiW is .uessursd by the degree f sepurat .or. accomplished *y fiber!: ir.g procures. The fibrous structure of asbestos 1* due to a highly developed prismatic c.l:.'.vr.gr, tho rpicings bet.-eoa cleavage planes bo,ng infinitesmxl or, at lexer, measurable by the sire of the ult irate pariiclc of fibor, which it ii.cmlculnbly crn.ll. Sub division therefore thoor:tlcally ray be continued almost indefinitely, tho flnm.-ca t:_U cum bo attiir.od depending on the del cccy of the tools used ar.d the shill of -ivanipv.l at ion. 2307 - 5 - 004565 u 1 . I | '8 A I I.C. 517 Varieties of asbestos and occurrences of the same variety vary markedly in the ir.e with which they can bo flberliei. . Eoae types' can be separated readily into slender fibers, while others are divided tilth difficulty and therefore appear as coarst-fibered .material. L'errlll lias neesured or.thophyllite fiberG down to 0.002 eva ir. diameter,5/ and the smallest measured dioucter recorded by Cirkel is 0.00075 rri.fi.' Apart iron strength end flexi bility the quality of iwbcstos it measured. to eone extent by the fineness of fiber attainable cr.:i by the amount of processing required to reduce it tc the fineness desired.. felt* a d lur.t erChry sot i 1e occurs ir various shades of green cr yrllc-TiGh freer.. - Chen ."icrriied Into a fluffy mas* til types of chrysotlle nre practically white, unless stained, by ir; unities. Amosite ranges from f/T.-ur or yellowish gray to nhite cud if relatively p- re is white when fibericed. Crccic-olite is li.vt-r.de r-blur, and tills color is maintained nhen tbo fibers arc separated, Ar.thcphy 11 it e ar.d tr'aolite are gray, greenish grey, or white, ar.d the sep&rt.ted fibers are whit. unless staining Impurities aro present. The luster.of asbestos usually is silky or pearly. . Heat Resistance.- Clrkcl states that (h.nadian chryrotilc withstands temperatures of 2,000 to 3,000 F. and the. a teenrrature cf 5,000 ?, pro duces co vluiblo effects on some varieties,J. It has been found, however, that when chrysotlle le heated to a high temperaturo Its water of crystalli zation lr. driven off anc. It becomes brittle. Anthophyllltc, tre.mollte, and amosite contain lor percentages of rater and withstand higher temperatures than oilier varieties. However, crocidollte, although having a low water content, Is easily fused Into a black magnetic cast. Hen*. Conductivity.- Asbestos does cot have low heal conductivity. Its v'.lut fer r.eat lr.sulaticr. is due to its noninflamability ar.d also to its fibrous structure, rhicl eic.pt it for manufacture into coverings that aro r.or.ccr.dcctcrs of heat V cause of their porcus nature.. 4'V*_?r*L*t'remolite and anthophyllltc arc highly resistant to acids. It is claimed tint crocidollte res 1stn che-.icals and sen .rater re markably well, Crxysot:ic i affected more readily by acids and other chemi cals than ore the amphitsle varieties. Electrical P.eslatai.ccVarieties of chrycotlie lowest in iren content are the most suitable fir electrical insulation, Arise..a chrysotlle is tuperlsr for this use. Aoparertly the iron content of .vcphlbcle decs not effect its use for tw.ls nurprie because crocidollte, rnich upon analysis shins a content of abcu* 35 percent Fe3, hre high electrical resistance. e : -i. Lr~>lo11 it ion, Hill" h 55 d` Pd., 1510, p. 6b 6 004566 iJ ) 1 I -i I I 8 A 2 I.C. 6017. i-i crochhlite as * silicate, rhereao In chrysotils it casaonly anpsars ns iron o.uid- Impurities. chzhical compos:?icu 7 e : ezical formulfs for the vrxious kinds of Asbestos rue given in ! h- s.rsh on varieties, Theoretical compe lit ion os calculated fros cko.niczl i rarely corrisnor.de with actual corpooition because nore or less i~ urity l alrays protest. The following ta'olo chore analyses cf repre sentative t srsoorcial fibc/s. Analyses of rcorescntr.tivc r.sbestjn sarnies, -percent sic2 a123 ?e23 ' U0 CaO UagO H,0 Sotal C ,.-sr *. he, lanadai/ j . - . .v..< t . z - U r Crtcissl,.- Cepe Cc 1 ory'i/ . ^*v-.. . -w <. . , , lr .cl/**** 7re->ol ; 'talfi/.. 40.3S 0.21 56.40 1.15 SI .10 ___ 49.72 5.72 58 w0 5/5.32 1.35 C.65 45.06 13.45 59.39 ___ 11.0 23.5C 0.50 ___ 1.63 99.76 35.fO 2.30 6.90 3.90 100.00 .... 57 .CO 3.77 1.65 ---- 2.29 100.15 - -- -- " 22.75 10.65 .50 93.02 0., Ckrysotllo Asbestos in Canada: Canada Dept, kir.es, linnet 7, 1931, p. 20. , 0. J., Asbectps, Talc, and Soapeto.ne Deposits of Georgia: Ocol, . Georgia Bull. 29, 1914, p. 79*. 1-J -:~n, A. Asbestos in the Union of South Africa: Afrir u> >1. Survey tea. 12, 1916, p. 19. ' p 22. t. 1, p. 2w. Union of South *23* USES 'V. .is of use nrbestos f.'.lls into tvso principal closets - spinning ar.i r.e..opii-.r.i ; fiber. Spinning fiber comprires the longer grades of chrysotii , c":to, oassite, and, e::ceptis.xlly, trerolitc, Eoncpl.ir.ir.g fiber T-r:rthi hsrtor ^relee of this* varieties and bsth the lo;ic and short , of : n.^-lllte end related anhibo-o vs.ijslo*. :a., til- l: -hr br-j;--'-. ] / If ^ * e* - r * * . use of minx, in': asbestos is for thr -.v.uf.'.cture of auteno- mines tr.C clutch fusings. As rue i as /9.C09,OCD feet of -s hav? leer, rads in a single /car In the Ur.lteu State*. i<g of .so'eetos cloth covered r<th ruetvr cr-.ent cor.su-.c lrrgc -x.iag f her. Ache at os of *pi ...ir.;, grade is uacd alts fer if : lrc-_. sof the..ter c.u tales uid see ery; blna'-ets; r.'.t tresses; gljvcs, r.r.d thsos; rs.os; .'--'.tens; let-/;i'. ;s; h.rluct r.; '.i--- cits for carryi.v; ..ot rate; ini t; bs.-.iccd ard roven tap"*; ryjs: t:!::; rspe; >.' list 1 7 e use of asbestos in alr- - 7 (2337) 00456V v I r- 'i~r i I I TT 3 I.C. 6617 Ilona?Inning fiber is used principally in the heat-lnsulntIon and roofing trade*, although large quantisles of the bettor gradoe are uaod for calcine eolded brake lli.lngs. On nccr.nl of its heat-insulating and f ire-re si sting properties asbestos paper, Manufactured in the same ray ns ordinary paper, ie used for calcine three-ply air-cell and similar pipe covering; at shooting botneen floors; as lining for sieves, luatcrn, filing cabinets, soldiers' hclcotc, mufflers for automobiles, druj controllers in sulphite mills, autoiobile radiatcr covers, and tubes l'cr electric wires; and in cany other cays. A widely used pipe covering consists of about 15 percont asbostos and E5 per cent ccgncsia. Compressed sheete of asbestos combined with ceaer.t are used extensively for corrugated sheeting, wall board, millboard, lumber, and floor tile end as lining fer cafes, stoves, heaters, electrical switch bo::es, garages, hoeds of automobiles, and ovens. Asbestos compound* are used to uor.e extent in automobile bodies, Asbestos-ccmcnt pipes are finding increas ing use for water and gas naius and sewers. They ore resistant to acids, nab corrosive, relatively nonconductive. of heat and electricity, light in weight, and so elastic tliat traffic vibrations ere unlikely to cause lealengo. Moreover, they are easily ploced and Joined,. A standard European pipe con sists of 80 percent cement ard 20 percent asbestos. hoofing sillagios consist lag of about E5 percent portland cement and IS percent asbestos are used extensively. Large quantities of short fibers aro consumed in the manufacture cf plastic fireproof cements 'used for boiler, pipe, and furnace covering. They alto aro usod in fireproof paints,-in arc welding, for protecting the surface of metal chs&thlng, and as a constituent of acphalt-roof costings. Hie stronger grades of anthophyllite aro used for making acid filtere, stoppings in combustion .tubes, wicks for producing flames by saturation with mineral salts, fireproof supports and prctcctorn, and other chemical-laboratory equipment, tfenk and brittle arphlbcle asbestos is used in making plastic eeaonts ar.il as an ingredient in acoustical and other wall piaster, cement flooring, and battery boxes, but it cannot bo used in shingles and compressed sheets where dibar strength is Important, Uahy industries uso asbestos for hundreds of minor puu'posen. UIIJIX HITHODS Asbestos deposits in the various localities differ wLdoly In cisarccter, and methods of mining depend greatly on conditions of cccurrer.ee. In some plr.cos the rode Is blasted in open quarrlce and leaded with power shovels in much the siai ray at llmestcno or trap rock it quarried for tho production of crushed stone. In other deposits elaborate syctcc* of underground mining have beet, devoloped. General methods followed it the principal districts are outlined briefly. Arison*..- In Arisona ctrysotllo asbostos occurs .n relatively thin veins paralleling lL-.estr.no beds and therefore is nine;! in .`rifts and tunnels. As tne veins are only a fen Inches thick nuch waste roc'.: mutt be reinovcd to g.vc rcrhlrg space. A typical wining motiwd is to rr. r.tal . a tur.r.cl roof cloio to thr asbestos tor.o and tc etch the asbestos o.i-o o large canvas. As tho Macs arc fur from railroads'md rvrkats the sits, t fibers can eenreely bo sold at a profit, and crudr s co.'.ctltuto vlrt oily the entire outpu.. S^vorrl r:d7 -C- 004568 'Ini I 8 <J A ) ' I.C. 6317 thousand feet of tunnels have been driven In rslr.ee on Ash Creel: end at other points in the southern pert of the State. Vermont.The chry.siiie asbestos quarries of Vorr.or.t are situated at an elevat lor. of 2^500 feet on tho south side of Belvidor* mountain approxi mately 15 mile*. from -iyde P.irl:, the nearest railway station. As the rod: outcrops at this hti.it, very little stripping lo necessary. The quarry face Is about 125 fret: high, ar.d Individual bcndies are 1? to 15 feet high. Blast holes axe surd: -ith hammer drills. An electric louer shovel with a le-cubic yp.rrt dl-pcr is use.' for loading into .'>-ton site-dump cars tiiat disc.oargc ever n grizzly into a 25- by 3c--:.ich Jxr crusher' at the mill. 4* ' r1 r\d ).i rvlend.- Mass-fiber anthoph/llito, ;ho variety found lu Of. re -:-1 usually occurs ir. jeexets or lense confined for the nost part to surface zones; it therefere is quarried in shoilov eper. pits. As operations c-e sunll, the material ic loaded by hand into snail cars tiiat convey it to tie xill or to the transshioping point. Quarries nt Sail Mountain and 5!:: ly-rr.od, On., a re of this type. Slip-fiber mtiiophyllite, on the other luind, occurs in narrov shear zones, which necessitate excavation in narrow opencuts or underground warmings. The Pylesville (lid.) operations aro examples. ' QuebecStripping is "a serious problem in the Quebec district as over burden raises from 6 or 8 feet to n .taxinrun of 125 fact in depth. For nany years, asbestos rp.r. obtained from laxye open-pit quarries served by overhead cableways. Abcut 1527 methods were modified by the introduction of nen equipment'- cranes cr poic: shovels were introduced for loading, locomotives vi-re uced for hauling cars on the quarry floor, and cable moists removed -.me care fro:: the pits up inclined planes or through turx.cls. Power-shovel i aiding, crushing, ar.d subsequent recovery of crude fiber from pichir.g belts are gradually replacing liar i coobirg of crudes ir. the opiarry. T!:is method recucrs cost? but tends tr reduce recovery of crude. The principal raisons for the chr.-.j.c were (1) decreasing r.arliets for cnodcs die to ti:e introduc tion of. molded brt-.c llr.in. s; (2) ir.creasiaj supalier of crudes from "h jdcc'.a, t..c Union o: Sou'h Africa, and P.ussia; (2) n decreasing proportion cf erodes In the red:; and (4) lor^cr prices for crudes. A still later d'vrlcw:cr.t In the Quebec district ic the introduction cf shri.-usage sloping. ?hc stone is drawn through civ.tec directly into boxes '.rax.-.ed by- ,\end cr elcctri . loccmotivoc throv. ` lur.r. Is leading tc the open pit, frem which the matert il is hoisted by high-speed c.Vole-.rays. The most recent ir.ncvr.tion is an 1 ibr.ratc ol iel:-cavi:.g rycten at the King mine of -.he Asbestos Coo-porat lor.,- ltd., patterned after the system employed in some of the Ariscna, copier mines. Satisfactory -pc.-e t ion las teei attain'd, ;uod 1 aing coots are consiuer: oly lc.er t'--nn there jccori-c for '.h; irr iniicgcticoir.g 'i'.i.od. I'otalls of the presort have be n y .lithed.i/ -0- 034569 0 :) I i I I 8 4 5 I.C. 6B17 ?hodslf\.- Two mining methods - quarrying and slirlnkags stoplng - aro used at the Shaboni, the largest asbestos aim la Bhodesla. Tho quarrying nethod It peculiar In that tha rock It broken In open pits but removed through vertical siinfte. Shaft or Blazes are eunk In rawe 5-0 to 60 feet apart and eo u.ccted with crosscuts at a lcwcr level. The rock around then le drilled and blasted and tho fiber cobbed from the broken fragments. In order t^iat the fiber r.iay be broken as lit tlo as possible light per.der charges are fired in ohallow holec. The broken rock is thrown into the shafts which aro kept nearly full, drawn into cars on the level below, ar.d token to the mill for extraction of the short fiber or recovery of the long fiber cot renored in cobbing. The cobbed fiber is thrown down a separate shaft. The shafts are also employed for disposal of wasto and f~T * ra lrogo. The shrinkage-stoplng 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. Ur.jonef Scuth Africa.- The largost asbestos nines in the Union of South Africa ore those producing chrysotile in the 3arbertcn district of the Trans vaal. The asbestos-bearing serpentir.o occurs in two zones. Tho upper cne, known as the "ribbon reef", contains short-floer vcir.B, and the lower cno provides long fiber. Thj Belt dips 10 to 2C, and underground mining is practised. The rilbon reef is stoped first, snd at a lator stags tho rock carrying long fiber is removed from the footrsll. Two largo ralnen have been developed In this territory, Tho Hew Amianthus mine la corked on several levels. In 1920 it extend'd down tho dip a distance of 1,650 feet from the outcrop. In the same year the Uunr.ikUyburg mine comprised about 3,300 feet of underground working** In the Carolina district of the Transvaal chrysotilo occurs in crossfiber veins occupying a 5-foot cone of altered dolomite dipping 0 to 15, liir.es have been operated since 1905 end- have reached a depth of 300 feet. Amosite of the Lyder.burg district of the Trnr.cvnal occurs in bended ironstones that have beer, highly folded ar.d contorted. The fiber-bcarlng beds usually stand at anglos ranging fron 15 to vertical. As they are ur.tu 1 tod fer open-pit working underground mining Is generally fallowed, rpere the bed* are intercectod by transverse vnlleyr tunnels arc drivoa along the strUco, and the fiber-bearing rock Is stoned out at various levels. 0utcrcc6 aro numerous ove: a wide area, and fiber Is obtained fron many mires werked at relAtivoly shallow depths, Tho largest mines art; the Zgr.cp and the Anosa situated noar Pergo. In thie region the flber-boa"ing zone dips from 15o to 223. The Zgncp mine is worked on seven levels. .* vertical shaft 215 feet deep serves the sevcr.tr. level and is connected with the sixth by a crosscut. The Anota nine, as described by Eall In 1930, comprised 11 drifts starting frem tho outcrop ar.d roaring from 80 to' 1,140 feet in length down tie dis. An Inclined s)*aft 320 feet lorg corresponds to.a vertical depth of 2C,0 feet. - 10 - (2337) 004570 I.C. 6817 Crocidolits (blue a*ber.tos), which It associated with omosltc In the territory north of the Olifmts River, lc mined Ir. trail underground rexicings, Crncidclitc also occur# over a wide nron lr. the Prieska and Xunraaji dlttrict# of the Cape cf Coed Hex e. The vein# are lrregiJar arid discontinuous, and systematic mining cannot bo followed generally, tiucli of tiie fiber 1* obtained free; trail eper. pits or from t'rrallou mine* norl.ed by native*. A fon nrlnee have been worked to depth* of 250 feet with drift* over 1,000 feet long. Hall deccribes in coclderable detail aabestq* mining In South Africa./ ' Russia.- The aobeeto* leposit* of the Bnjanova district have a thin over burden. lard methods of removal were first employed, out po;7er shovels or hydraulic aetliods have superseded thoa to quite ar. enter.!;, llore than 20 shallow open quarries were worked for nany years. Up to 1S29 drilling was tho only nechanleal process used, all other operation* being conducted with hand teole, Owing to inadequate ailling facilities, hand picking became ar important concentration process, and only one fourth to one fifth of the rode quarried was sent to.`-he mill, Tho cverage fibor content of the rock mined was only about f por:ent, but because of the concen tration at mined by hand picking that sont to ;ho mill was 22 percent. The first rteps toward more complete aechanizaticn were taken in 1229, with the installation of 2- to 4-ton capacity sverhead cableways with fixed fjot towers ana traveling head towers. Theso core supplemented by Inclined hiulagemays served bp electric hoists. The rede was bleated in benches 5 to 6 meters high .and classified Into crudos, mil] feed, and waste. In 1929 two shafts rere sunk and connecttd nlth a haulrgo level at a depth of 50 meters. They wero designed for flory-holo mining, which proved uneconomical, This method was supplemented atd largely superseded in 1930 by electric-shovel loading in opou pits rith transport by locomotives to in clined nr.ulcgerays, up which cars are tnkon by electric hoists, lining costs are eitlm.itad at about 75 cents a metric, ton.of rock. Details of quarrying and mining methods Lave boer. cuo.alied by Su Iicystr.^2/ Cyprus.- Chrycotilc asbestos occurs or. the slopes of kcur.t Trucdos in irregular veins travertin/: oerper.tino formed by alteration of olivine. Tho expansion accompanyi:ig metauorphlsn of original olivino resulted in excessive fracturing, which makes excavation easy. The workings consist of open-pit terraces rsnchl;v a tsnnimun height of 2i0 feet, kuck of the rock is so frac tured a.id decs:a;s6od thr.t it can be broken with picks without the aid of ex plosives, 3e:crs 1927, wh*;> co...prosced-air drills vrre introduced, the harder rock was (k illed fsr blasting by hand methods. 1fr.cn 40-pound hand hr-unor drills ore used 3-lr.di Lolee rargl'.g in dopth from 8 to 12 feet oro sunk at the rnto of about 10 feet aa hour. Tlie larger .uartes of barren rock are re moved as waste, and l lbev-cenrirg material is turned over to facilitate drying Ja the hot sun. It is ther pnered over gravity screens, and that pasting 57 kil, 1. L.( ju'j..sto* in ths'Xv.Tn of Scr.t'hlfr'Va*: Ceo'l. Survoy of South Africa kem. 12, 2d cd., 1C"0. 10/ Ru Xcyu-r, 7alter A., Ulniag Ar.uer.tos in U.S.S.R.j 2r.g. and kin. Jcur., vol. 13d, Seatouber l')53, pp, 573-381. 2337 - 11 004571 1!) < i I ! I 8A7 I.C. 6817 through an IB-run nesh screen :ind retained on a 5-cn screen (about one fifth of t.ie total material quarrlel) it tent to tho nillt for recovery of the fiber. Overtire rock rotalred on the upper tcrecn and sand', passing tho lcrer tefeen are tramed to naste heaps. 'Quarries are norked frera liarch to Deccnbor. In 1927 appr.-'ninitcly 6,000 workers were ecr loyed in the qvarries, and about 1,500,000 tons of rock nere broken. Cperatiins have been conducted on a ouch tseller scale sir.co that year, J'urther deta Is of quarry o:otkods are riven by Tnitncrth.il/ Production consisted exclusively of short fiber until 1934 when according to report a ana11 quantity of spinning fiber was shipned. WORLD PRODUCTION 'The follctrir.g table compiled by the Bureau <t Uinee shews production of asbtssos by ccuntries for 5 years. 11/ rr.ituortn, M., C>-prus anc Its Asbestos Industry: llining Ling. (London)* vol. 39, September 1323, pp. 143-150,. 2337 12 - 004572. 0 n .j i) ! ;i Ul 8 ) 8 X.C. M17 EaxHOESi'iSiiia.-fi_*Ai.t91, 1929-33. In metric tong (Coqplltd by ll. T. Lotus, of ths Bureau of Uinos) Courtryl/ 1923 1930 1331 1932 1933 Africa: Portuguese last Africa 2/ 16 (2/ (2/ Southerr. Rhodesia .... Swaziland ........................ Union of South Africa, 30,677 .29,970 34,260 17,491 2i,eio 14,221 14,302 g ' 10,951 27,331 27 14,412 Australia: Wen South TTalcs ........... 0 _____ 2/ South Australia ,......... 6 20 2/ Weste rn Australia-., 144 116 112 2/ Canada^/ .......................... .. 219,641 149,047 111,562 141,006 China .......................... Cyprus^/ .......................... .. . -315 5,467 264 3,628 2/ l,f26 y 2/ Finland ................................... 1,1C8 581 756 2/ France ................................. 503 2/ :-3/ 2/ Gr .-eco ..................................... 2 10 2/ 2/ Ir.d.a, Brltith 34 6 91 2/ ::::::: 851 1,000 632 1,0C0 ' 1,284 2/ 1,000 , 2/ Russia ..................................... 54,083 64,674 2/ 2/72,000 Turkey .................... .. 2/ 4 : -58 2/ United States lu* >.ta. 3.848 .2,920 . 3,229 4.305 u In addition to the.countries list eu, tlada^ascir reported a production of 545 l:llcgro.-as of asbestog in 1329 Ho .enplcltation of .the deposits has been reported since t.iat dace. % Exports. ............... *.* . Data not available,....................' 1 Exclusive of sand'Afld (nvtl, the production of which is reported ai felloes: 1329, 17,215 tons; 1330 ,'35,249 tons; 1931, 6,.r:43"'tor.o; 1332, 3,151 tons; 1S32, 5,850 tons. Approximate production. % Tear ended Septeaber 30. Estimated sroductlon. These figures Include both lon and short fibers *>f all varieties of asbestos. The output In Rhotesla ar.d the Union cf South Africa consists prin cipally of spinning fiber anl the lonjcr and core valuable sratlcs of mill fiber, bec-.usc tho locol dattir'd for s'.tort fibers Is a-.ill ar.d tho price too Ion to Justify shipment to foreign raricets. Duetix, on the ether hand, has developed Important asbeeto*-products Industries that utilize larpe quantities of short fiber fren the Urals. Cw.As. has s*all local demand for short fiber, but the industrial centers of the eastern United Hates provide a ready rar^t, and for this rascn the shorter grouts constitute a larqo proportion of tho asbestos production, 2337 - 13 - 004573 1 I i I 18 19 I.C. 691? The outsat of nott countries showed a oteady and pronounced decline fiom 19.29 to 1933, but that of countries for which figure* are available short t. general increase in 1933. Busnia it an exception; ltt production tiiort a carhod increase from 1929 to 1933. Thit country it now on* of tho world't large it producers cf asbestot. rami co;:suuptio:i It li core difficult to determine the consumption of asbestos than ltt prrdue*.ion. Production plus imports minus exports of raw asbestos for any ycur-zay net glvo & true picture of consucntion because stoclrs may bo hold ever for 6c=e tine end reexported, or material cor tuned may consist of stocks terror ted in a previout year. The following table tnlcen- from AsboEtoslS/. furnishes Interesting data on consxnption. The figures nrre compiled by "*ropag" Asbest-ur.d Zrsimport Hamburg, Cernany, frm data supplied by t.-.e ministerial and consuls offices of the countries concerned." 7or 1931 total coniurn*. lm at given In the tab .o (2-3?,053 metric tcr.t) r-.y:ciL-..'. closely the world production (299,933 ".Ctrl, tens) at compiled by tr.o ?urc ,u of hires. The agn ctent 1* much closer ha.i 'ould be cr.w'ctcd i*..cn i. r; at i or. t ir. stocks t.nd cot : i.il in traosit are ec side.el. J--.e 1334. I. \ !; 004574 J J I i I I 860 Z.C. 6817 The Unitod States lcais all countries in asbestos consumption. On a ton nage bests, Busria stands second and England third. Otcor ieportant consusing -ountries are Fiarxe, Gcrr.iny, 3cli.:iU3, and Japan... The following table presents on independent co.-spils.tlon of apparent world onsusptlon for 1931. Figures for production were ta):er from Bureau of lines : Ir.erals yearbook, 1932-33 and t-iose for inports'end exports from The Minoral 2 :dustry of the British Umpire and Foreign Countries, 1530-1932, published by ' tc Imperial Inst, ituto, x/ondon. The figuros fer apparent consumption agree 3 ascnably well with those of the preceding table. florid consurrot ton of asbestos, 1031 (lorr tons) Country Produc tion Import e Experts Apparent consumption!/ V 1 ted Stnte e ... C made ........................................... > z * ................................................................. ted Ilngmmm .. flC# # IV83 iy...................... la......... .. tugal ................ herland* ..... sail; .................. rjuy ;i -.ria.................. V*7 .................. ho Slovakia ,, tsrland ..... nd.................... on .......................................... . uad ...................................... -alia ....... *r C.i i a # ................................................ W ISSSSSSSSf 2,682 14b,790 63,655 S84 ------------------ (2/> ----- 622 `------------------ ----------------- . ---- -- ----------- -- -- 72 128 35,463 60 121,751 -- 7,127 19,433 (2/) 12,411 5,194 3,225 79 267 693 9.C53 4,992 2,356 5,263 1,135 395 978 953 Cl 1,200 --:------------ 1,281 '100 400 1,530 :42,355 13,030 770 -- 237 * 141 180 5 ----'` 553 81 ------------------- 461 9 6 -- 2 -- -- 38,553 -------------- --- tal apparent nsumpticn.. "" " ~ 1 j .djcttoa plu* Lmpbr'.t minus cuports. '. ! ij. r.;t available. . '..noted. - 15 - 123,103 4,345 50,625 8,111 18,663 5/ 10,000 12,174 5,675 3,045 79 262 G93 9,100 4,911 2,356 4,C02 1,126 389 978 951 633 2,328 ------------- 260 1,291 100 400 255,390 004575 :.C. 6217 POLITICAL AIZ) CCLE3GIAL COT.kOL B-jssI.3 only of the four leading producing cou: tries hat important asbestos-prod-. ;ts CA.-iufa.cturir.g plant*, The other principal producing countrie* - Canada, Bhodela, and tho Union of South Africa - utilize a very c-nll proportion of -e asbestos they produce. On tho other hand, the principal asbestos-consuming countries - the United State*, England, France, Germany, Belgium, and Japan - produce no asbestca or only mail tomato*. A large pro portion of all asbestos mined tnereforo enter* Litemational trade, and ell the principal nation* ere interested in foreign *ourc* of ripply and their availability in tlcei of emergency. Political Control.- Three of the four largo asbestos-producing countries of the norld - Canada, Rhodesia, and the Union of South Africa - aro in the British Empire, lioderately important deposits in Cyprus and Australia and mall deposit* In India, Uen Zealand, and Uenfouni-and also are under British political control. The largest deposits outside.the 3rltish Enpiro are tnose of thoT-oviet Un .or., nhile others of considerable importance are under the dominion of the Ur. .tei States, Italy, and Finland. Relatively smell deposits are controlled politically by Argentina, Austria, Brasil, Bulgarii, Chins, Mexico^ Portugal, Spain, Scitzerland, and Turkey. Concerclal Control.- All asbestos-producing companies in the'United'State., .except the 3ear Canyon Asbestos Co., Globe, Arts., apparently orb' controlled by United StAtes capital. The Boar Canyon Asbestos Co. is a subsidiary of the lensbey ilattison Co., Ansler, Pa., the controlling Interest b'i nhleh'ras aco.uirec.'in 1933 by Turner L Uetrall, Ltd'., Lcndon, England. . Ccssereial control of the Canadian nines is diverse. The'largest' company, Asbestos Corporation, Ltd., is controlled by English, Canadian,' and Ur.itod Ctater. capital. The Johnson Co., the pioneer operator, probably `is controlled, ty Cnn.vCi.cn capital. Tho Quebec Asbestos Corporation, Ltd., ovr.od.by tho ?:.: 1 Ip Carey Uir.'afacfcring Co,, Cincinnati, Ohio; tho Cano.dinn Uonns-llanvllle !c., Ltd., a subsidiary of Jchrs-Manvillc, Inc,, Terr York; and the Uicolet -t.beotoo Mines, Ltd,, a trsill i er York fira, aro dominated by United States tnoital. Ti;e Bell Asbestos Mires, Inc., operated by the Ueosbcy L Ilattison V>,, Ambler, ?a., lc now contrcllod by Turner 'Tewall, ltd., London, -nglnr.d, Tho rmership of the Canadian companies .therefore evidently is`divided among English, United States, and Cstadian capital. The amounts cf capital inverted ty England and the Unitod Stat< s aro approximately the same, riiile tlid^ Cnaadlaa investment is less. British capital prodor.lniv;e* In all the asbestos-producing companies of Thodtsia and the Union of South Africa, The Soviet Union controls both politically and coivnjrclally nctlvitioc in the asbestos industry of tho Urals. ., I Tho one company operating Ir. Cyprus is cont-ol.cd b' British capital. :.\*37 - 16 - 004576 u U'!) I.C. 6617 7or cuny years a British company controllemost cf the production cf Italy, tat since 1029 ar. Italian co.T-,-\ny ha* operated tno 3ala<i"sro Hires t/herc the chief production Is now cer.terod. Practically all the deposit* of Australia are controlled by Zn^lish or Australian capital. pof-cisr tsads Iwrmrt sThe foljocir,' table cor-piled fro- Bureau of L!lne9 statistic* show* imports of asbectoo 1; to the United State* Per 5 years. It include* or.ly the crude o.-.d nilu fibers that constitute, on the basis of value, the principal internr.tior.Inl triu.o lr. asbestos. Import* rf asbe< tee Into the Uni_teo States. 1930-53 (Crttde and mill fiber cnly) C ountry ofshipment 1929 Snort tens Value 39 "0 Short tons Value 1931 Short tons Value Africa ............. Canada ............. Germany ........... Itcly ............... Soviet Pussta, United Zi.'.edoK m p. ' ~ 1 < -> ........... C ,204 100,033 1,174 123 252 226 348 $Z, 163,754 ,121,330 361,446 31,257 131,290 65,437 55,125 3,210 70,957 390 48 4,534 410 "- $730,274 3,656, lf>5 63,397 8,753 660,539 113,634 -- "" - " ** 1,337 47,340 110 19 2,103 953 $189,349 2,123,746 10,700 9.C55 104,271 166,465 Country of 1 r.iz.T.er*t *l \ i kiTic* ............. i G< ncar.y ...... ! -cly ................ Soviet ?.-ssia. J '-bitted hlr^do.'. I * ............... 1 2337 1932 Short tons Yeluc 1,326 31,064 1 85 1 $117,774 1,335,799 30 9,627 ------- - 399 - 17 - 1933 Short tons ... , Veluo 2,324 4C.S16 4 17 176 1 $234,557 2,337,946 669 C.929 17,339 587 a - ___ 004577 iif rt I I 853 I.C. 631? Countries of sMocent as fiven In the precedinf table are not r.ecoasarily the countries of orifcln; they ray roorosent the lost porta of ehimsnt. To determine the crlfincl sources it coy be assured that aooroxi.xtely nil the asbestos shipped fron Cerrar.y is of Tusslen orifin nnd the t the fiber ahlooad fron the United j.lnfdom end Belgium res produced in Adrien. Ths follc-inf trblo shora annunl imports by countriee pr orifin for 5 yee rs. 3Q'-rcfl3 of asbestos Iroorted into the '!hi ted Smtea, 1039-33 (C.Jde er.d mill fiber onlf) Jource 1929 Short tons Value 1930 1931 Short tons 1 Short Value tons Volus l:ic>i ........... Ctnadn ........... J.viet pussie Ttuly ............. 7oU:l ____ ^ourc A.'rlci ........... Cunrdc ........... lo.'iet Pusslc Ituly ............. Total e,773 102,033 1,426 12.3 112,360 i'2,234,316 6 .121,330 472,726 31,227 9 ,909,639 3,620 70,957 4,924 48 70,549 'P43.95? 3,ote,i9: 744,450 9,752 S,253,301 2,290 47.34C 2,299 19 51,947 V55.R14 2,123,740 114,971 9,955 2,604,390 .i i .... 19 12 1-- Short tons Value 1,327 31,054 1 85 32,477 .113,173 1.235, 709 30 9. 627 1,413, 629 193: 3hort tons *i<) |1t9APw 48,916 19?. 1 17 51,440 Velue i ,i ;4 2,337,946 19,0C? 9,929 2,600,027 1 The folloring tcble shots 'he cercentnjes cf tof. pu ntity and relue of total cnr.uii iuoorts for 5 19 - D04578 rri"; | | f S~A-------- I.C. 6817 ?crcentiyre of crude aid mill-fiber asbestos obtained fron -.>j of t.ie -rl.icia-'l fcrlyn _srurc e s. 1929-33 Cource Africa ........... Canada ...... Sr viet P.ussia Italy ............. i ! 1 ?, i 1 102') ! 1 Value | 1030 J ) Quantity Value 1731 Quantity Value 7.8 60.6 1.3 .1 25.7 68.7 5.3 .3 4.P 83.2 .6.2 . ;1 16.1 69.-t 14.1 .2 1931! t% . 1933 4.4 91.1 4.4 .1 13,7 81.6 '4.4 " .3 Average, far the 5 years Source Quantity V* lue Quantity V&luo Quantity ' 'Value .Ica Canada ........... Soviet Prussia Italy ............. 4.1 95.6 ------ .3 0,4 91,0 -- .6 4.5 95.0 .4 .1 9.0 89.9 ,7 .4 f.l 92.3 ` 2.5 .1 14.6 eo.i 4.9 .4 It ray be obcerved tiux* larjorto from Africa a.-.d Pv.seia are orach higher ir. value t.ian In quantity. Tills it due to the fact that only the higherpriced crude fiber* can be Imported profitably from such distent sources. On tno other hr.ua, the percentage in quantity of Canadian fiber eucecds its percentage i.i value bocauso the bepcsits are near canruvir^; centers, pcrcittlnj tile 1-ncrtation of laryo quantities of the shorter ..illl fibers. As cany tua.nufocturer s nf asber.tos products are interacted chiefly in sources of ruoply of the iil^ncr-Tade set:::il:*; fleers m attempt lies been . i.do t> estimate tiie tcnnujis received in recent year-, from ths orlr.ciy.il producing centers. T.-.e f al.oni\- table s.tcws t'u- ;. -r,; or. irate tinar^c: of itr.r.iuy; autectos received v.r.1 ly f: :' 1021 to 1.0 :: :i Canada, and huisia rad the jercer.t.* . utal err crur.try furnished. - 13 - i t\ r rm I.C. 6617 Year Principal reurecsgf nInning asbcsto imrrtcd Into the Inltrd States. 1924-33 Cana daiy Africa Russia Short tons Percent of total imports Short tons Percent of total imports Short tons Pci cent of total .inports i?24 ;-- 1?25 ......... 1926 ......... 1927 ........... 198 . 1920 ......... 197 1 ......... ' O~ W'.*pCr | * 1 | 12,463 17,543 17,081 14,953 15,163 IE,363 6,473 f, 770 4,290 (4/) . 80 79 78 66 62 64 50 60 . 77 3,051 4,390 4,747 6,096 C.778 6,770 3,021 2,290 1,327 2,325 20 20 21 2'7 28 31 21 20 23 "- . 56 191 349 1,782 2,339 1,426 4,924 2,296 (2/) 182 (2/) 1 1 7 10 5 29 20 (2/) '1 1j Pierres fer Canadian tonnagos ore approxisate. The following text ex plains methods cf determination. . <.. 2] Loss than 0.5 porcoat., , ... 2/ Less than 1 ton. . . ..... 4/ Eatn not available. For the purpose of calcule tlon Canadian spinning fiber includes crude r: . 1, crude no, 2, crude rur.-e f-cine, and the highest-grr.de mill fiber, rhlch 11:: co 1720 has been designated "spinning fiber." Pl^wcs f-r the production of Canadian asbestes by g.-rdcc are vuslishsd annually, but irrport figures re r 2 act cegregated by gra.'cs u ntil 1027. Prcm 1024 to 1^*7 it is assumed t* i'U. report* cf spinning fib-r bore the sane relation to toial iriorts that IT'' iu:t ip.-. of epi.inir.g fiber b? re to total proauetirn. I: other rordr, if 65 percent of the total Canalis i production (exclusive of material classed as "sand, gravel, and Bteno") r is inported into the United Staton, it Is asvuned that 35 percent of tho scin..ing fiber produced in Canada rat shipped to tho United States. Since 1527 the tonnages cf crude and ulll fiber lino ted from Canada 'm/e bocr. recorded, but rjin.tln; fiber still is not reusr.ed separately* To determine this tor.-age therefore 1* ! asn-ned tljt the vr.riwvs grades cf mill fibers (spinning* rhlr.gU, and paper rtoch) are imported ir. t.c ratio cf tnsir preduetton; that is, If 25 percent of the r.ullsirch produced is of a-l.'.nli.g grads It ie assumed tr.it 25 percent cf tho rlHs'oc': i"portcd it spinning fiber. Th; quantity if spinning fiber thus calc dated is then ailed to irr.o.ts of Canadian crulcs to tu'rlve at the total into, ts rf mir.r.lnj :.::r trrr. -a. 7 20 - 004 580 0 0 v) I TS 1 I T"S'i I.C. 6817 Approxinntoly all imports from the other foreign countries aro regarded as spiking fiber. Russian imports In 1931, hocever, rere separated Into crudes and sill fiber, the latter being regarded ae nor.splnr.ing. 3y referring to the preceding table it ray be observed that Canada sup plied about 00 percent of tlio total innorts frsa 1924 to 1926. Ia 1927, hocever, this percentage dropped to 6d, ti.d in 1932 It nas only 50. In 1232 the Dominion again furnished over three fourths of imports, but the total quantity from all sources was except!onally Ion. Africa supplied about 20 percent of the total each year, except during the period 1927-23, nhen the. proportion nas' considerably higher. Since 1926 lnports from Russia liave been considerable; in 1930 Russia supplied r.ioro than one fourth of tho requirements rf the United States. Practical cessation of imports from Russia in 1932 ray bo attributed to the embargo plrcod on them during an investigation conducted by the United States Tariff Commission. Although the embargo ras lilted, imports in 1923 v/cro of no consequence. A string movement torurd importation from the more distant sources of supply has been evident in 1934. Of crude fibers imported curing tho first 7 months, Africa -upplied E< percont, Russia 24 percent, and Canada 22 percent. Zxmorts.- Large quar.titios cf asbestos prcducts are exported from the United States. The statistics also shorn domestic exports of unmanufactured asbestos as indicated in the follorlng table. Recent oxperts -under this category have consisted mainly of shingle stoch of foreign origin blended in the United States and shipped raialy to Japan, llcxico, ar.4 Rurcpo. The ex ceptionally high valuo of exports in 1928 Is due to a large rhipnent of Russian asbestos to Gerrr.117." Statistics cf the Department of Commerce nlso shon ahimmonto of obout 1,090 tons of foreign crude rx.d urm.-umfacture4 asbestos annually 'indor "experts rf foreign merchandise," Those represent Iransshipments of Canadian material via American ports. Asbestos (unmanufactured) rmmortod frem tho `Jr.ited_5tr.tes, lOKrlS........................ Tear 192< ......... 1S25 ......... 1326 ......... 1027 ......... 1C2C ......... Short tons Valuo i 1 Tear i 1 3Uor# tons S 1,::79 1.1C9 1.1C4 309 50 *23,153 70,646 85,332 42,744 346,632 192?......... 1930 ......... 1931......... 1932 ......... 1333 ......... 709 771 1,714 1,707 1,370 Value $103,467 93,318 122,321 94,936 68,521 2337 - 21 004581