Nabokoite

General Information:
 Chemical Formula:
Cu++7Te++++O4(SO4)5·KCl
 Composition:
(Molecular Weight = 1,191.29 gm)
Potassium 3.28 % K 
Copper 37.34 % Cu
Tellurium 10.71 % Te
Sulfur 13.46 % S 
Chlorine 2.98 % Cl
Oxygen 32.23 % O 
 Empirical Formula:
Cu7TeO4(SO4)5KCl
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
yellow or yellow brown.
 Density:
4.18
 Diaphaniety:
Transparent
 Hardness:
2-2.5 - Gypsum-Finger Nail
 Luster:
Vitreous (Glassy)
 Streak:
yellowish brown
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