Tenorite
| Tenorite | |
|---|---|
| General | |
| Category | Oxide mineral | 
| Formula | CuO | 
| IMA symbol | Tnr | 
| Strunz classification | 4.AB.10 | 
| Crystal system | Monoclinic | 
| Crystal class | Prismatic (2/m) (same H-M symbol) | 
| Space group | C2/c | 
| Unit cell | a = 4.6837(5) Å b = 3.4226(5) Å c = 5.1288(6) Å; β = 99.47°; Z = 4 | 
| Identification | |
| Color | Steel-gray, iron-gray, black | 
| Crystal habit | Lathlike crystals, curved, scaly, dendritic; commonly pulverulent, earthy, massive | 
| Twinning | Common on {011}, forming stellate groups; lamellar | 
| Cleavage | Poor to indistinct | 
| Fracture | Conchoidal to uneven | 
| Tenacity | Brittle; flexible and elastic in thin scales | 
| Mohs scale hardness | 3.5–4 | 
| Luster | Metallic to earthy | 
| Streak | Black | 
| Diaphaneity | Opaque, thin flakes transparent | 
| Specific gravity | 6.5 | 
| Optical properties | Biaxial (+) | 
| Pleochroism | Distinct; light to dark brown | 
| References | |
Tenorite, sometimes also called Black Copper, is a copper oxide mineral with the chemical formula CuO. The chemical name is Copper(II) oxide or cupric oxide.