Tellurobismuthite
| Tellurobismuthite | |
|---|---|
Tellurobismuthite. Locality: Kutemajärvi mine, Orivesi, Western and Inner Finland Region, Finland | |
| General | |
| Category | Sulfide mineral |
| Formula | Bi2Te3 |
| IMA symbol | Tbi |
| Strunz classification | 2.DC.05 |
| Crystal system | Trigonal |
| Crystal class | Hexagonal scalenohedral (3m) H-M symbol: (3 2/m) |
| Space group | R3m |
| Unit cell | a = 4.43, c = 29.91 [Å]; Z = 3 |
| Identification | |
| Color | Pale lead-gray; white in polished section |
| Crystal habit | Foliated masses and irregular plates |
| Cleavage | Perfect on {0001} |
| Tenacity | Flexible, sectile |
| Mohs scale hardness | 1.5 – 2 |
| Luster | Metallic |
| Streak | Lead gray |
| Diaphaneity | Opaque |
| Specific gravity | 7.815 |
| References | |
Tellurobismuthite, or tellurbismuth, is a telluride mineral: bismuth telluride (Bi2Te3). It crystallizes in the trigonal system. There are natural cleavage planes in the (0001) direction as the crystal is effectively lamellar (layered) in that plane. The Mohs hardness is 1.5 – 2 and the specific gravity is 7.815. It is a dull grey color, which exhibits a splendent luster on fresh cleavage planes.