Tenorite

Tenorite is a copper oxide mineral with the simple formula CuO. 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.
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General Information:
 Chemical Formula:
CuO
 Composition:
(Molecular Weight = 79.55 gm)
Copper 79.89 % Cu
Oxygen 20.11 % O 
 Empirical Formula:
CuO
 Environment:
Secondary copper mineral.
 IMA Status:
Approved IMA 1960
 Locality:
Bisbee, Arizona, USA.
 Name Origin:
Named after the Italian botanist, M. Tenor (1781-1861).
Physical Properties:
 Cleavage:
None
 Color:
black or steel gray.
 Density:
6.5
 Diaphaniety:
Opaque
 Habits:
Scaly - Morphology like fish scales., Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite)., Massive - Uniformly indistinguishable crystals forming large masses.
 Hardness:
3.5-4 - Copper Penny-Flourite
 Luminescence:
None.
 Luster:
Earthy (Dull)
 Streak:
black
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