Bismuthinite - Encyclopedia
Class : Sulfides and sulfosalts
Subclass : Sulfides
Crystal System : Orthorhombic
Chemistry : Bi2S3
Rarity : Common
Bismuthinite is an accessory mineral of high temperature hydrothermal mineralization associated with granitoid intrusions, notably tin and tungsten deposits, which are also found in pegmatites (Madagascar), auriferous veins (Salsigne, France), and fluorite - siderite veins. It frequently accompanies native bismuth, arsenopyrite, cassiterite and wolframite. Its name derives from its chemical composition : bismuth. It is quite rarely presented in squat prismatic crystals with finely striated needles, reminiscent of the stibnite. Bismuthinite usually occurs as lamellar aggregates, cleavable foliated, fibrous or grainy masses, also similar to stibnite. It is a lead-gray to pewter-white mineral, often dull yellow or iridescent on the surface, which readily changes to bismutite on outcrops. It is a bismuth ore, often recovered as a by-product of gold or tin.
Main photo : Bismuthinite from Tazna Mine, Potosi, Bolivia © Fabre Minerals
Bismuthinite in the World
Twinning and special crystallizations
No twin known for this mineral species.
Fakes and treatments
No fake identify for this mineral species.
Hardness : 2 to 2.5
Density : 6.78
Fracture : Irregular
Trace : Gray
TP : Opaque
RI : -
Birefringence : -
Optical character : None
Pleochroism : None
Fluorescence : None
Solubility : Nitric acid
Magnetism : Diamagnetic
Radioactivity : None