SKUTTERUDITE. 147 Fracture uneven, flat conchoidal. Light steel-grey, inclining to tin-white, and sometimes to lead-grey. Sometimes acquires a dark grey, or iridescent tarnish, n = 5‘5. o = 6'92.. ,7'3. Chemical characters the same as those of smaltine, except that the solution in nitric acid yields a copious precipitate of oxide of iron 011 the addition of carbonate of lime. RAs, where It is Co and Ee. Analyses of safflorite a from Schneeberg, by E. Hoffmann; & by v. Kobell:— a I Cobalt . 13-95 9-44 Iron . . 11-71 18-48 Nickel 1-79 — Copper 1-39 trace Bismuth o-oi l'OO Arsenic . 70-37 71-08 Sulphur 0-00 trace found in very small crystals, reniform and botryoidal ;s having a columnar structure, compact and disseminated. SKUTTERUDITE. — Hartkobalterz ; Hausmann. Skutterudit; Haidinger. Cubic. a 100, o ill, d Oil, p 122 FIG. 131. aa' 90° 0' 00 70 32 on 64 10 dd' 00 0 da 45 0 pa 70 32 pci 48 11 Cleavage, a, distinct; d, traces. Fracture flat conchoidal. Opaque. Lustre metallic. Tin-wdiite, inclining to lead-grey ; sometimes with a tarnish like blued steel, n = O'O. G = C74... 0'84. In the matrass yields a sublimate of metallic arsenic. In the open tube yields a copious sublimate of arsenious acid, leaving a rose-red powder. The reactions before the blowpipe are the same as those of smaltine. Co 1 As 3 , cobalt 20'77, arsenic 79-24. n 2