Ikunolite

General Information:
 Chemical Formula:
Bi4(S,Se)3
 Composition:
(Molecular Weight = 967.29 gm)
Bismuth 86.42 % Bi
Selenium 6.12 % Se
Sulfur 7.46 % S 
 Empirical Formula:
Bi4S2.25Se0.75
 IMA Status:
Approved IMA 1959
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
lead gray.
 Density:
7.8
 Diaphaniety:
Opaque
 Hardness:
2 - Gypsum
 Luster:
Metallic
 Streak:
dark gray
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