Page:Encyclopædia Britannica, Ninth Edition, v. 16.djvu/412

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394 MINERALOGY 202. COLORADOITE, HgTe . Massive and granular. H. =3; G. =8 63. Metallic. Iron-black. Conchoidal fracture. C.c.: 61 mercury, 39 tellurium. Colorado. 203. MOLYBDENITE, MoS . Hexagonal (?). Crystals OP, ocP; and OP, ooP,P. Generally scaly. Cl. basal, perfect; sectile and flexible. Feels greasy. H. = ltol 5; <t. =4 6 to 4 9. Lead-grey with red tinge ; grey streak on paper, greenish on porcelain. B.B. colours flame siskin-green ; on charcoal yields sulphurous fumes, and forms a white coating ; in warm nitrochloric acid a greenish, and in boiling s. acid a blue solution. C.c. : 59 molybdenum, 41 sulphur. In granular limestones, and in Fig. 345. granites in Sutherland, Ross, Aberdeen, Argyll, and Kirkcudbright; Shap in Westmoreland, Caldbeckfell in Cumberland, Arendal, Zinnwald, Mont Blanc, Maine, Connecticut, Yea in Victoria. Used for preparing blue carmine, for colouring porcelain. 204. LAURITE, (RuOs) 2 S 3 . Cubic. Crystals 0, ooOoo ; ooQ3, ooOoo . Cl. octahedral. H. = 7 5;G. =6 "99. Metallic, bright. Dark iron-black. Powder grey. Brittle. C.c.: ruthenium 65 18, osmium 3 03, sulphur 3179. From platinum grains, in Borneo and Oregon. 205. REALGAR, AsS. Oblique prismatic. ooP (M) 74 26 ; P<; () 132 2 , ooP2 (I) 113 16 . Crystals (fig. 346) generally prismatic; sometimes massive. Cl. basal, also clino- diagonal ; fracture splintery ; sectile. H.=l-5 to 2; G. =3-4 to 3 6. Trans parent to opaque; resinous. Aurora-red ; streak orange-yellow. C.c.: arsenic 70, sulphur 30. Nagyag, Felsb banya, St 7 Gotthard, Vesuvius. 206. ORPIMENT, As 2 S 3 . Right prismatic. ooP 117 49 . Fre quently foliated. Cl. brachydiagonal ; striated vertically ; sectile and flexible. H. =1-5 to 2; G. =3 4 to 3 "5. Semi- F . _ transparent; resinous to pearly. Citron- yellow and orange-yellow. C.c. : arsenic 61, sulphur 39. Servia, Kapnik, Andreasberg, Solfatara, Zimapan in Mexico. 207. DIMORPHITE, As 2 S 3 . Right prismatic. H. = 1 5; G. =3 58. Orange-yellow. Solfatara. 208. STIBXITE, Sb 2 S 3 . Right prismatic. P polar edges 109 26 and 108 21 ; ooP 90 54 . Crystals (fig. 347) generally prismatic. Cl. brachydiagonal, perfect; sectile. H. 2; G. =4 6 to 4 7. Brilliant lead-grey, often tarnished. C.c.: antimony 71 8, sulphur 28 2. Maisley, Banffshire ; Harehill, Ayrshire ; Glendinning, Dumfriesshire ; Endellion and Padstow, Cornwall ; Wolfs- berg, Harz ; Przibram, Schemnitz, Auvergne, Spain, America, Melbourne. Chief ore of antimony. 209. BISMUTHINE, Bi 2 S 3 . Kight prismatic. ooP 91 30 . Crystals prismatic, striated ; also granular and foliated. Cl. brachydiagonal ; sectile. . ._ , OA0 . H. - 2 to 2 -5 ; G. = 6 -4 to 6 6. Lead-grey. F ^ 347 < 8 P- 208 >- C.c. : 81 2 bismuth, 18 8 sulphur. Caldbeckfell (Cumberland), Redruth (Cornwall), Riddarhyttan and Bastnaes (Sweden), Alten- berg, Haddam (Connecticut), Ballarat (Victoria), Bolivia. 210. FRENZELITE, Bi 2 Se 3 , or 2Bi 2 Se 3 + Bi 2 S 3 . Right prismatic ; ooP 90. Needle crystals, and massive. Cl. brachydiagonal. H. =2 5 to 3; G. =6 25. Bluish grey; streak greyish black, shining. Lustre metallic. Malleable. C.c.: bismuth 67 38, selenium 24 13, sulphur 6 6. Guanajuato (Mexico). SULPHUR SALTS. 211. GUEJARITE, Cu 2 S + 2Sb 2 S 3 . Right prismatic. oP 101 9 . Cl. brachydiagonal. G. =5-03. Steel-green, with bluish streak. C.c.: copper 15 "5, anti mony 58 - 5, sulphur 25. Guejar in Sierra Nevada. 212. MIARGYRITE, AgS + SbS 3 . Oblique prismatic, C 81" 36 . P 90 53 ; -P 59 59 . Crystals pyramidal, or tabular (fig. 348) ; massive ; sectile. H. =2 to 2 5 ; G. =5 2 to 5 - 3. Metallic adamantine. H.=3 5; frey; streak cherry-red. C.c.: 37 silver, 41 antimony. 22 sulphur, reiberg, Przibram, Potosi. 213. MOROCOCHITE (Silber-Wismuth Glanz), AgS + BiS 3 . Massive. Colour grey; streak light green. G. =6 92. C.c. : silver 28 3, bismuth 547, sulphur 17. Morococha in Peru. 214. SARTORITE, PbS + As.,S 3 . Right prismatic. Crystals slender ; oP 123 20 . Cl. OP. H. -3; G. =5-39. C.c.: lead 42 68, arsenic 30 93, sulphur 26 39. Biunen- thal in Switzerland. 215. ZINCKENITE, PbS + SbS 3 . Right prismatic. ooP (d) 120 39 ; Poo (o) 150 36 (fig. 349). Crystals acicular ; vertically striated, and twinned 3 or 6. Sectile. H. =3 to 3 5 ; G. = 5 3 to 5 35. Steel-grey to lead-grey ; with blue tarnish. C.c. : lead 35 9, antimony 42, sulphur 22 !. "Wolfsberg. 216. EMPLEOTITE, CuS + Bi 2 S 3 . Right prismatic. Tin-white. Saxony, "Wiirtemberg, and Copiapo. 217. WOLFSBBRGITE, Cll 2 S + Sb 2 S 3 . Right prismatic. <x>P 135 12 ; o>P2 111. Crystals tabular; also tine granular. Cl. brachydiagonal, perfect ; fracture conchoidal oruneven. H. =3 5; G. =4748. Lead-grey to iron-black, sometimes iridescent; streak black, dull. C.c.: 25 4 copper, 49 antimony, and 25 6 sulphur. Wolfsberg. 218. BERTHIERITE, FeS, SbS 3 . Massive ; columnar or fibrous, with indistinct cleavage. H. => 2-3; G. =4 to 4 3. Dark steel-grey, reddish. Tintagel and Padstow in Cornwall, Auvergne and Anglars (Creuse) in France, Briiunsdorf in Saxony. In France used as an ore of antimony. 219. PLAGIONITE, Pb 4 Sb 3 . Oblique prismatic, C 72 28 120 49 . Crystals thick, tabu lar (fig. 350), minute, and in druses. Cl. -2P, perfect; brittle. H. =2-5; G. =5-4. Blackish lead-grey. C.c.: 41 lead, 38 Fig. 349 (sp. 215). P 134 30 and 142 3 ; -2P antimony, Wolfsberg. and 21 sulphur. 3Cu,S 220. KLAPROTHITE, + 2Bi 2 S 3 . Right prismatic; long striated crystals; ooP = 107. Wittichen, Fig. 350 (sp. 219). Bulach. Schirmerite, from Colorado, 3(Ag,,Pb)S + 2Bi 2 S 3 , with G. = 674, is similar. 221. BINNITE, 3CuS + 2As,S 3 . Cubic. Typical forms 006, 202; 0, ooOoo, 606; 404, 10010 30|. H. =4-5 ; G. =4-48. Metallic. Black. Binnen. 222. JAMESONITE, 3PbS + 2Sb.,S 3 . Right prismatic; oP 101 20 . Crystals o>P, <Poo, long- prismatic, parallel or radiating. Cl. basal perfect, ooP and brachy diagonal imperfect; sectile. H. =2 to 2 5 ; G. = 5 5 to 57. Steel- grey to dark lead-grey. B.B decrepitates, fuses easily, and wholly volatilizes except a small slag. Sol. in warm n. acid. C.c.: 44 5 lead, with 2 to 4 iron, 34 9 antimony, and 20 6 sulphur. Cornwall, Estremadura, Hungary, Siberia, and Brazil. 223. DUFRENOTSITE, 2PbS + As 2 S 3 . Right prismatic. ooP 93 39 . Generally in thick rectangular tables. H.=3; G. =5-56. Lead-grey. Brittle. Binnen, St Gotthard. 224. FRIESLEBENITE, 5(Pb, Ag 2 )S + 2Sb a S 3 . Oblique prismatic, C 87 46 . ooP 119 12 ; Poo 31 41 (fig. 351) in prisms with curved reed-like faces, and strong vertical striae. Twins intersecting ; also massive. Cl. ooP, perfect; fracture con choidal or uneven ; rather brittle. H. = 2 to 2 5 ; G. =6 2 to 6 4. Steel-grey to dark lead- grey. C.c.: 22 5 silver, 32 4 lead, 26 8 anti mony, and 18 3 sulphur. Freiberg (Saxony), Hiendelaencina (Spain). 225. PYRARGYRITE, 3Ag 2 S + Sb 2 S 3 . Hexagonal rhombohedral ; R (P) 108 42 ; -iR13758 ; OR; -2R(r);R3; ooP2(s); and ooR (I). Crystals prismatic (fig. 352); twins common, of various kinds; also massive, dendritic, or investing. Cl. R, rather perfect; fracture conchoidal to uneven and splintery; Fig. 3ol (sp. 224). sectile. H. =2 to 2 5. Crimson-red to blackish lead-grey ; streak cochineal to cherry-red. Huel Brothers and Huel Duchy in Fig. 348 (sp. 212).

Blackish lead-grey to steel ] Cornwall, Andreasberg, Freiberg, Johann-Georgenstadt, Annaberg,