Aleksite

General Information:
 Chemical Formula:
PbBi2Te2S2 (?)
 Composition:
(Molecular Weight = 944.49 gm)
Bismuth 44.25 % Bi
Tellurium 27.02 % Te
Lead 21.94 % Pb
Sulfur 6.79 % S 
 Empirical Formula:
PbBi2Te2S2
 IMA Status:
Approved IMA 1978
 Locality:
TL: Russia, Alekseev mn, Stanovoi Range
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
steel gray.
 Diaphaniety:
Opaque
 Hardness:
2.5 - Finger Nail
 Luster:
Metallic
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