Document MoK0rbkqqRkV5eLx4bGLnpny9

A TEXT-BOOK OF M I N E B A L O G -Y W ITH AN EXTENDED TREATISE ON CRYSTALLOGRAPHY AND PHYSICAL MINERALOGY 4# 1 ft BY N E W EDITION, ENTIRELY REWRITTEN AND ENLARGED WUf nearly 1000 fig u re s and a Colored m ate NEW YORK JOHN WILEY & SONS L ondon : CHAPMAN & HALL, Limited J THE NEW YORK PUBLIC LIBRARY 58!)378 A8TOR. LENOX AND TILDEN FOUNDATIONS. R 19,3 L ` Copyright, 1898, ` . BY .*3 d WARD S. DAJTA: *rr rtnm iu PrrM *ferrt Hrammoad*ud Sfaaforfc p r - ' - r - , p r yuj: Ci 1) ui` 'Xt'rj Vu.iX, s PREFACE. U^> % T h e remarkable advance in the Science of Mineralogy, during the years that have elapsed since this Text-Book was first issued in 1877, has made it necessary, in the preparation of a new edition, to rewrite the whole as well as to add much new matter and many pew illustrations. The work being designed chiefly to meet the wants of class or private instruction, this object has at &nne determined the choice of topics discussed, the order and fullness of treatment and the method* of presentation. In the chapter on Crystallography, the different types of crystal forms are described under the now accepted thirty-two groups classed according to their symmetry. The names-given to these groups are oased, so far as possible, upon the characteristic f o r o f each, and are intended also to suggest the terms formerly applied in `accordance with tho principles of hemihedrism. The order adopted is that which alone seems .suited to the demands of the elementary student, the special ,'arid maihep-atically simple groups of the isometric system being described first. Especial prominence is given to the " normal gro u p " under the successive systems, that is, to the group which is relatively of most common occurrence and which shows the highest degree of symmetry. The methods of Miller are followed as regards the indiceB of the different forms and the mathematical calculations. In the chapters on Physical and Chemical Mineralogy, the plan of the former edition is retained of presenting somewhat fully the elementary prin ciples of the science upon which the mineral characters depend; this is par ticularly tru e in the department of Optics. The effort has been made to give the student the means of becoming practically familiar with all the modern methods of investigation now commonly applied. Especial attention is, therefore, given to the optical properties of crystals as revealed by the micro scope. F urther, frequent references are introduced to important papers on the different subjects discussed, in order to direct the student's attention to the original literature. The Descriptive part of the volume is essentially an abridgment of the Sixth E dition of Dana's System of Mineralogy, prepared by the author (1892). To this work (and future Appendices) the student is, therefore, referred for fuller descriptions of the crystallographic and optical properties of species, for lil iv PREFACE. analyses, lists of localities, etc.; also for the authorities for data here quoted. In certain directions, however, the work has been expanded when the interests of the student have seemed to demand it; for example, in the statement of the characters of the various isomorphous groups. Attention is also called to the paragraph headed " Diff.," in the description of each common species, in which are given the distinguishing characters, particularly those which serve to separate it from other species with which it might be easily confounded. The list of American localities of minerals, which appeared as an Appen dix in the earlier edition, has been omitted, since in its present expanded form it requires more space than could well be given to it; further, its reproduc tion here is unnecessary since it is accessible to all interested not only in the System of Mineralogy but also in separate form. A full topical Index has been added, besides the usual Index of Species. The obligations of the present volulne. to well-known works of other authors--particularly to those of Grotb^kod'ltQsenbusch--are too obvious to require special mention, . ^ ^ a ^ t h o r intist/ho_wever, express his gratitude to his colleague, Prof.dLlV/ J^irssou, who has given him material aid in the part of the work dealing With the optical properties of minerals as examined under the microscope. He is also indebted to Prof. S. L. Penfield of New Haven and to Prof; ELr A* Miers of Oxford, England, for various valuable suggestions. * 7*'** N ew H aven, Conn. , 1898. * 1*. TABLE OF CONTENTS PAGE Introduction........................................................................................................................... X PART I. CRYSTALLOGRAPHY. General Morphological Relations op Crystals....................................................... 5 General Mathematical Relations of Crystals........................................................ 22 L Isometric System............. ............................................................................................ 83 1. Normal Group (1). Galena Type..................................................................... 33 2. Pyritohedral Group (2), Pyrite Type................................................................ 43 8. Tetrahedral Group (8). Tetrahedrite Type...................................................... 46 4. Plagihedral Group (4). Cuprite Type.............................................................. 50 5 Tetartohedral Group (5). Ullmannite T ype..................................................... 51 TL T etragonal Sy st e m ..................................................................................................... 58 1. Normal Group (6). Zircon Type........................ ............................................... 53 2. Hemimorphlc Group (7).................................................... ..................... ............ 59 8. Pyramidal Group (8). Scheelite T ype.............................................................. 59 4. Pyramidul Hemimorphic Group (9). Wulfenite Type................................... 61 5. 8phenoidal Group (10). Chalcopyrite Type..................................................... 61 6. Trapezohedral Group (11)........................... ...................................................... 63 7. Tetartohedral Group (12)..................................................................................... 63 H I. H exagonal System......................................................................................................... 65 A: Hexagonal Division..................................................................................................... 66 1. Normal Group (13). Beryl Type........................................................................ 66 2. Hemimorphic Group (14). Iodyrite Type....................................................... 71 8. Pyramidal Group (15). Apatite Type............................................................... 71 4. Pymmidal-Iiemimorphic Group (16). Nephelite Type.................................. 73 5. Trnpezoliedral Group (17)................................................................. 73 B. Trigonal or Rhombohedral Division......................................................................... 74 1. Trigonotype Group (18).................... 74 2. Rhombohedral Group (19). Calcite Type......................................................... 74 8. Rhombohedral-Hemimorphic Group (20). Tourmaline Type....................... 79 4. Tri-rhombohedral Group (21V Phenacite Type........................... ............... 80 5. Trapezohedral Group (22). Quartz Type.......................................................... 82 6# 7. Other Groups (23) (24).................... .................................................................. 84 Mathematical Relations of the Hexagonal System................................................ 84 IV . Orthorhombic System........................................................... 89 1. Normal Group (25). Barite T ype...................................................................... 89 2. Hemimorphic Group (26). Calamine Type...................................... 95 8. Sphenoidal Group (27). Epsomfte T ype.......................................................... 96 Mathematical Relations of the Orthorhombic System.................... ................... 96 v v i TABLE OF CONTENTS. PAGE Y. Monoclinic System......................................................................................................... 98 1. Normal Group (28). Gypsum Type................................................................... 99 2. Hemimorphic Group (29)...................................................................................... 103 3. Cliuohedral Group (30). CHnohedrite Type.................................................... 104 Mathematical Relations of the Monocliuic System................................................ 104 VI. Triclinic System........................................................................................................... 106 1. Normal Group (31). Axinite T ype................................................................... 107 2. Asymmetric Group (32)........................................................................................ 109 Mathematical Relations of the Triclinic System.................................................... 109 Measurement of the Angles of Crystals................................................................... 112 Compound or T win Crystals............................................................................................. 118 Examples of Important Methods of Tw iuning................................. ................... 123 Regular Grouping of Crystals.................................................................................. 131 I rregularities of Crystals............................................................................................... 132 1. Variations in the Forms and Dimensions of Crystals....................................... 133 2. Imperfections of the Surfaces of Crystals.......................................................... 136 8. Variations in the Angles of Crystals................................................................... 138 4. Internal Imperfection and Inclusions.................... ............................................ 138 Crystalline Aggregates..................................................................................................... 142 PART II. PHYSICAL MINERALOGY. P hysical Characters of Minerals.................................................................................. 145 I. Characters depending upon Cohesion and Elasticity.............................................. 14C II. Specific Gravity, or Relative Density....................................................................... 15( III. Characters depending upon Light............................................................................... 160 General Principles of Optics..................................................................................... 160 Optical Instruments and Methods............................................................................ 180 General Opticul Characters of Minerals................................................................... 186 1. Diaphaneity..................................................................................................... 186 2. Color................................................................................................................ 186 8. Luster ............................................................................................................ 188 Special Optical Characters of Minerals belonging to the different Systems.. . . 192 A. Isometric Crystals.......................................................................................... 193 B. Uniaxial Crystals........................................................................... 193 General Optical Relations.......................................................................... 193 Optical Examination of UniaxialCrystals................................................. 197 C. Biaxial Crystals............................................................................................. 208 General Optical Relations.......................................................................... 203 Optical Examination of BiaxialCrystals................................................... 210 IV. Characters depending upon H eat.............................................................................. 231 V. Characters depending upon Electricity and Magnetism........................................ 284 VI. Taste and O dor........................................................................................................... 288 PART III. CHEMICAL MINERALOGY. General P rinciples of Chemistry as A pplied to Minerals................................. 289 Chemical E xamination of Minerals................ 254 Examination in the Wet Way ................................................................................ 254 Examination by Means of the Blowpipe............................................................... 256 TABLE OF CONTENTS. Vll PART IV. DESCRIPTIVE MINERALOGY. PAOS N ative E lements................................................................................................................... 271 Sulphides, Sklenides, Tellurides, etc......................................................................... 282 S u l p h o -Sa l t s ............................ 306 Chlorides, Bromides, I odides, F luorides..................................................................... 317 Ox id e s .................... 324 Carbonates.............................................................................................................................. 353 Silicates................................................................................................................................... 368 T itano-Silicateb, Titanates............................................................................................... 485 N iobates, Tantalateb........................................................................................................ 489 P hosphates, Arsenates, Vanadates, etc...................................................................... 494 N itrates............................................................. 517 Borates.......................... 613 U ranates............................................................................................................ 521 Sulphates, Chromates, etc................................................................................................ 523 T ungstates, Molybdates.................................................................................................... 539 Oxalates, Mellates............... 542 H ydrocarbon Compounds........................................................'. .......................................... 543 A PPEN D IX A. D rawings op Crystal F igures, and of P rojections................................................. 547 A PPEN D IX B. T ables to be Used in the Determination op Minerals....................................... 557 General I ndex................................................................................. I ndex to Species........................................................................... 570 579 SILICATES. 479 Deweylite. A magnesian silicate near serpentine but with more water. Formula perhaps 4MgO 3iSi0,.6H,0. Amorphous, resembling gum arabic, or a resin. H. = 28*5. G. = 2*0-2 2 Color whitish, yellowish, reddish, brownish. Occurs with serpentine In the Fle.msthal, Tyrol; also at Texas, Penn., and the Bure Hils, Md. Gymnite of Thomson, nam ei from yvfivoS, naked, in allusion to the locality at Bare Hills, Md., is the same species. Genthite. Nickel Gy (unite. A gymuite with part of the magnesium replaced by nickel. 2N i0.2M g08S i09.6Hs0 . Amorphous, with a delicate staluciilic surface, intrusthig. H. = 3-4; sometimes very soft. G. = 2*409. Luster res nous. Color pile applegreen, or yellowish. From Texas, Lancaster Co., Pa., in thin crusts on chromite. Garaierite. Noumeite. An important ore of nickel, consisting essentially of a hydrated Bilicate of magnesium and nickel, perhaps H s(Ni,Mg)S 0 4-f- aq, but very variable in com position, particularly as regards the nickel and magnesium; not always homogeneous. Amorphous. Soft and friable. G. = 2 3-2*8. Luster dull. Color bright apple-green, pale green to nearly while, lu part unctuous; sometimes adheres to the tongue. Occurs in serpentiue rock near Noumea, capital of New Caledonia, associated with chromic iron ami steatite, where it is extensively miued. A similar ore occurs at Riddle in Douglas County, southern Oregon; also at Webster, Jackson Co., N. C. TALC. Orthorhombic or monoclinic. Rarely in tabular crystals, hexagonal or rhombic with prismatic angle of t>0. Usually foliated massive; sometimes in globular and stellated groups; also granular massive, coarse or fine; fibrous (pseudomorphous); also compact or cryptocrystalline. Cleavage: basal, perfect. Sectile. Flexible in thin laminte, but not elastic. Percussion-figure a six-rayed star, oriented as with the micas. Feel greasy. H. = 1-1*5. G. = 2*7-2*8. Luster pearly on cleavage surface. Color applegreen to white, or silvery-white; also greenish gray and dark green; sometimes bright green perpendicular to cleavage surface, and brown and less translucent at right angles to this direction; brownish to blackish green and reddish when impure. Streak usually white; of dark green varieties lighter than the color. Subtransparent to translucent. Optically negative. Ax. pi. [a . Bx _L c. Axial angle small, y -- a = 0 035-0*050. V ar.--Foliated* Tale. Consists of fobs, usually easily separated, having a greasy feel, and presenting ordinarily light green, greeuisli white, and white colors. G = 2 55-2*78. Massive, Steatite or Soapstone (Speckstein Germ.), a. Course granular, grayish green, and brownish grny in color; H. = 1-2*5. Pot stone is ordinary soapstone, more or less impure, b. Fine granular nr cryptncrystalline. and soft enough to be used as chalk; as the French chalk, which is milk-white with a pearly luster, e. Indurated tale. An impure slaty talc, harder than ordinary talc. Pseudomorphous. a. Fibrous, fine to coarse, altered from enstntite and tremolite. b. liensselaerite, having the form of pyroxene from northern New York and Canada. Comp.--An acid metasilicate of magnesium .H^MgJSiO^or IlqO.SMgO^SiO, = Silica 63*5, magnesia 31*7, water 4*8 = 100. The water goes off only at a red heat. Nickel is sometimes present in small amount. P y r., etc.--In the closed tube B B., when intensely ignited, most varieties yield water. In the platinum forceps whitens, exfoliates, and fuses with difficulty on the thin edges To a white enamel. Moistened with cohalt solution, assumes on ignition a pale red color. N< t decomposed by acids. Renssclaeiite is decomposed by concentrated sulphuric acid. Diff --Characterized by extreme softness, soapy feel; common foliated structure; pearly luster; it is flexible but inelastic. Yields water only ou intense ignition Obs.--Talc or steatite is a very common mineral, and in the latter form constitutes extensive beds in some teirions. It U often associated with serpentine, talcose or eldoritic schist, and do'omite, and frequently contains crystals of dolomite, breunnerite, also tttbesius, actinoliie, tourmaline, magnetite. Steatite is the material of many pseudomorphs, among which the most common are those after pyroxene, hornblende, mica, scapolite, and spinel. The magnesian minerals are 480 DESCKIPTIVE MINERALOGY. those which commonly afford steatite by alteration; while those like scapoliteand nephellte, which contain soda and no magnesia, most frequently yield pinile~1ike pseudomorpba. There are also steatitic pseudomorphs after quartz, dolomite, topaz, chiastolite, staurolite, cyanite, garnet, vesuvianite, chrysolite, gehlenite. Talc in the fibrous form is pseudomorph after enstatite and tremolite. Apple-green talc occurs at Mt. Greiner in the Zillerthal, Tyrol; in the Valais and St. Gothard in Switzerland; in Cornwall, near Lizard Point, with serpentine; the Shetland islands. In N. America, foliated talc occurs in Maine, at Dexter. In Vermont, at Bridgewater, handsome green talc, with dolomite; Newfane. In Mass., at Middlefield, Windsor, Stan ford, Andover, and Chester. In R. Island, at Smithfield, delicate green and white in a crystalline limestone. In N. York, at Edwards, St. Lawrence Co., a fine fibrous laic (agalite) associated with pink tremolite; on Staten Island. In N. Jersey, Sparta. In Penn.t at Texas. Nottingham, Unionville; in South Mountain, ten miles south of Carlisle; at Chestnut Hill, on the Schuylkill, talc and also soapstone, the latter quarried extensively. In Maryland, at Cooptown, of green, blue, and rose colors. In N. Cur., at Webster, Jackson Co. In Canada, in the townships Bolton, Sutton, and Potion, Quebec, with steatite in beds of Cambrian age; in the township of Elzevir, Hastings Co., Ontario, an impure grayish var. in Archaean rocks. S B F IO U T B . Meerschaum Germ. L'cume de mer Fr, Compact, with a smooth feel, and fine earthy texture, or clay-like; also rarely fibrous. H. = 2-2*5. 0. = 2. Impressible by the nail. In dry masses floats on water. Color grayish white, white, or with a faint yellowish or red'* ' ^ Silica 60*8, magnesia 27*1, wat__ ,, er (2H,0), which is probably to be regarded as hygroscopic. Copper and nickel may replace part of the magnesium. P yr., etc.--In the closed tube yields first hygroscopic moisture, and at a higher tempe rature gives much water and a burnt smell. B.B. some varieties blacken, then burn white, and fuse with difficulty on the thin edges. With cobalt solution a pink color on ignition. Decomposed by hydrochloric acid with gelatinization. Obs.--Occurs in Asia Minor, in masses in stratified earthy or alluvial deposits at the plains of Eskihi sher; at Hrubschitz in Moravia; in Morocco, called in French Pierre de Savon de Maroc; at Vallecas in Spain, in extensive beds. A fibrous mineral, having the composition of sepiolite, occurs in Utah. The word meerschaum is Germau for sea-froth, and alludes to its lightness and color. Sepiolite Glocker is from a y m a , cuttle-fish, the bone of which is light and porous; and being also a production of the sea, " rieinde spumam marinam siguificaoat," sa>s Glocker. Connarite. A hydrous nickel silicate, perhaps HtNijSiiOit. In small fragile grains. G. = 2-459-2*619. Color yellowish, greeu. From ROttis, In Saxon Voigtland. Spadaite. Perhaps 5MgO 6SiOa.4HjO. Massive, amorphous. Color reddish. From Capo di Bove, near Home. 8A FO N ITE. Pfotine. Massive. In nodules, or filling cavities. Soft, like butter or cheese, but brittle on drying. G. = 2*24-2*30. Luster greasy. Color white, yellowish, grayish green, bluish, reddish. Does not adhere to the tongue. Comp.--A hydrous silicate of magnesium and aluminium; but the material is amorphous and probably always impure, and hence analyses give no uniform results. Contains SiO, 40-45 p. c., AIjO, 5-10 p. c., MgO 19-26 p. c., H tO 1921 p. c.; also F e,0,, FeO, etc. P yr., etc.--B.B. gives out water very readily and blackens; thin splinters fuse with difficulty on the edge. Decomposed by sulphuric acid. Obs.'--Occurs in cavities in basalt, dinbase, etc.; also with serpentine. Thus at Lizard Point, Cornwall, in veins in serpentine; at various localities in Scotland, etc.