Bismuthinite is a mineral consisting of bismuth sulfide (Bi2S3). It is an important ore for bismuth. The crystals are steel-grey to off-white with a metallic luster. It is soft enough to be scratched with a fingernail and rather dense. Bismuthinite forms a series with the lead, copper, bismuth mineral aikinite (PbCuBiS3). It occurs in hydrothermal... Found on http://en.wikipedia.org/wiki/Bismuthinite
Bismuthinite has the formulae Bi2S3 and a relative hardness of 2. It is an ore of bismuth, and the main commercial source of bismuth and occurs in veins that show definite relations to igneous rocks. Found on http://www.probertencyclopaedia.com/browse/HB.HTM