Tellurobismuthite

Tellurobismuthite is a rare mineral composed of bismuth, tellurium, and sulfur. It was first discovered in 1969 at the type locality, the Bismuth Mine in the Black Forest region of Germany. The mineral is named for its chemical composition, which includes tellurium and bismuth.

Tellurobismuthite crystallizes in the orthorhombic system and typically forms prismatic crystals. It is often found in association with other bismuth minerals such as bismuthinite and bismite. The mineral has a metallic luster and a dark gray to black color, with a black streak. Its hardness on the Mohs scale is approximately 2.5 to 3, and it has a specific gravity of around 7.5 to 7.7.

The chemical formula for tellurobismuthite is (Bi,Sb)2Te3S2. It is a member of the bismuthinite group of minerals, which also includes bismuthinite and jamesonite. Tellurobismuthite is relatively rare and is primarily found in hydrothermal veins associated with granitic intrusions.

Due to its rarity and the fact that it is not a commercially valuable mineral, tellurobismuthite is not widely collected or studied. However, it is of interest to mineralogists for its unique chemical composition and the geological context in which it forms.