Bismutite

Field of view: 10 mm. Bismutite associated with bismuth. The pinkish-silver grain exhibiting perfect cleavage is bismuth. The thin earthy black crust over bismuth is zavaritskite. The thin pale brown crust over zavaritskite is bismutite. The massive translucent part with a vitreous luster at the upper left is gangue quartz. The radial group of platy white crystals around bismutite is muscovite.

Recovered from a quartz vein of a pneumatolytic deposit formed near the boundary between welded tuff and S-type (Ilmenite-series) granite, members of a caldera complex.

Bismutite from this location was described in 1947.