Weissite

Weissite is a mineral consisting of copper telluride (Cu2-xTe). Weissite has hexagonal crystal structure. Its specific gravity is 6 and its Mohs hardness is 3. Occurrence is in Gunnison County, Colorado, Arizona and New Mexico in the United States. It is also reported from Kalgoorlie, Western Australia and Dalarna and Värmland, Sweden.
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General Information:
 Chemical Formula:
Cu1.9Te
 Composition:
(Molecular Weight = 248.34 gm)
Copper 48.62 % Cu
Tellurium 51.38 % Te
 Empirical Formula:
Cu1.9Te
 Environment:
Telluride ore deposits.
 Locality:
Good Hope and Mammoth Chimney Mines at Vulcan, Gunnison Co., Colorado.
Physical Properties:
 Cleavage:
None
 Color:
bluish black, dark blue black, or black.
 Density:
6
 Diaphaniety:
Opaque
 Hardness:
3 - Calcite
 Luminescence:
None.
 Luster:
Metallic
 Streak:
black
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