Bismite is a bismuth mineral, bismuth trioxide 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 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.