Famatinite

General Information:
 Chemical Formula:
Cu3SbS4
 Composition:
(Molecular Weight = 440.65 gm)
Copper 43.26 % Cu
Antimony 27.63 % Sb
Sulfur 29.11 % S 
 Empirical Formula:
Cu3SbS4
 Environment:
Antimoney (Sb) analog of enargite (arsenic-As).
 Locality:
Sierra de Famatina, La Rioja, Argentina.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[101] Good, [100] Distinct
 Color:
grayish black, dark pink brown, or steel gray.
 Density:
4.57
 Diaphaniety:
Opaque
 Hardness:
3-4 - Calcite-Fluorite
 Luminescence:
Non-fluorescent.
 Luster:
Metallic
 Streak:
black
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