Ores OF Bismuth

Native Bismuth, Bi.—This contains traces of As, Te, and S.

H = 2.0-2.5, G = 9.7-9.83. Color, silver-white, slightly tinged with red. Metallic lustre. Brittle when cold, but may be laminated when hot. Before the Bp. on Ch. behaves like pure Bi.

Bismuthite, Bi₂O₃ . 90, CO₂ . 7, H₂O . 3,—

H = 4.0-4.5, G = 6.9-7.8.

Usually of a white or light greenish color and vitreous lustre, in acicular crystallizations. In an ignition tube decrepitates, yielding water and turning gray. Before the Bp. on Ch. it fuses easily and is reduced to metallic globule, coating the Ch. with Bi₂O₃. With Na₂CO₃ it occasionally gives the sulphur reaction.