Algodonite

Algodonite is a copper arsenide mineral with formula: Cu6As. It is a gray white metallic mineral crystallizing in the hexagonal system. It has a Mohs hardness of 4 and a specific gravity of 8.38 - 8.72.It was first described in 1857 from the Algodones silver mine, Coquimbo, Chile.
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General Information:
 Chemical Formula:
Cu6As
 Composition:
(Molecular Weight = 456.20 gm)
Copper 83.58 % Cu
Arsenic 16.42 % As
 Empirical Formula:
Cu6As
 Environment:
Hydrothermal deposits associated with other copper arsenides.
 Locality:
TL: Chile, Algodones silver mn, Coquimbo
 Name Origin:
Named for the locality.
Physical Properties:
 Cleavage:
None
 Color:
gray, silver white, steel gray, or tarnishes dull bronze.
 Density:
8.38 - 8.72, Average = 8.55
 Diaphaniety:
Opaque
 Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., Tarnishes - Freshly fractured surfaces form a surface oxidation film,
 Hardness:
4 - Fluorite
 Luminescence:
Non-fluorescent.
 Luster:
Metallic
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