Tenorite
| Tenorite | |
|---|---|
| File:Tenorite - USGS Mineral Specimens 1083.jpg | |
| General | |
| Category | Oxide mineral |
| Formula | CuO |
| IMA symbol | Tnr[1] |
| 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 | [2][3][4] |
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.
Occurrence
[edit | edit source]Tenorite occurs in the weathered or oxidized zone associated with deeper primary copper sulfide orebodies. Tenorite commonly occurs with chrysocolla and the copper carbonates, azurite and malachite. The dull grey-black color of tenorite contrasts sharply with the often intergrown blue chrysocolla. Cuprite, native copper and Fe–Mn oxides also occur in this environment.[2]
In addition to the hydrothermal, tenorite also occurs as a volcanic sublimate from Vesuvius, Campania, and Etna, Sicily, Italy. As a sublimate it occurs with copper chlorides, alkali chlorides and cotunnite.[2] The Vesuvian sublimate occurrence was originally named melaconise or melaconite by F. S. Beudant in 1832.[5]
Tenorite was named in 1841 after the Italian botanist Michele Tenore (1780–1861).[4]