Fedotovite

General Information:
 Chemical Formula:
K2Cu++3O(SO4)3 or (K,Na)2(Cu,Zn,Pb)3S3O13
 Composition:
(Molecular Weight = 573.02 gm)
Potassium 13.65 % K 
Copper 33.27 % Cu
Sulfur 16.79 % S 
Oxygen 36.30 % O 
 Empirical Formula:
K2Cu3O(SO4)3
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
blue green or emerald green.
 Density:
3.205
 Diaphaniety:
Transparent
 Hardness:
2.5 - Finger Nail
 Luster:
Vitreous - Silky
 Streak:
light green
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