Laitakarite

General Information:
 Chemical Formula:
Bi4(Se,S)3
 Composition:
(Molecular Weight = 1,037.63 gm)
Bismuth 80.56 % Bi
Selenium 17.12 % Se
Sulfur 2.32 % S 
 Empirical Formula:
Bi4Se2.25S0.75
 IMA Status:
Approved IMA 1959
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
lead gray or lead white.
 Density:
8.12
 Diaphaniety:
Opaque
 Hardness:
2 - Gypsum
 Luster:
Metallic
 Streak:
grayish black
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