Junoite

General Information:
 Chemical Formula:
Pb3Cu2Bi8(S,Se)16
 Composition:
(Molecular Weight = 3,121.17 gm)
Copper 4.07 % Cu
Bismuth 53.56 % Bi
Lead 19.92 % Pb
Selenium 10.12 % Se
Sulfur 12.33 % S 
 Empirical Formula:
Pb3Cu2Bi8S12Se4
 IMA Status:
Approved IMA 1975
Physical Properties:
 Cleavage:
[???] Good
 Color:
gray.
 Density:
6.77
 Diaphaniety:
Opaque
 Hardness:
3.5-4 - Copper Penny-Flourite
 Luster:
Metallic
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