| Bismite | |
| Category: | Oxide minerals |
| Formula: | Bi2O3 |
| Imasymbol: | Bis[1] |
| Strunz: | 4.CB.60 |
| System: | Monoclinic |
| Class: | Prismatic (2/m) (same H-M symbol) |
| Symmetry: | P21/c |
| Color: | Grey |
| Fracture: | Uneven |
| Streak: | Grey to black |
| References: | [2] |
Bismite is a bismuth oxide mineral, bismuth trioxide or Bi2O3. It is a monoclinic mineral, but the typical form of occurrence is massive and clay-like with no macroscopic crystals. The color varies from green to yellow. It has a Mohs hardness of 4 to 5 and a specific gravity of 8.5 to 9.5, quite high for a nonmetallic mineral.
Bismite is a secondary oxidation zone mineral which forms from primary bismuth minerals.
It was first described from Goldfield, Nevada in 1868, and later from the Schneeberg District, Ore Mountains, Saxony, Germany.