Zoubekite

General Information:
 Chemical Formula:
AgPb4Sb4S10
 Composition:
(Molecular Weight = 1,744.33 gm)
Silver 6.18 % Ag
Antimony 27.92 % Sb
Lead 47.51 % Pb
Sulfur 18.38 % S 
 Empirical Formula:
AgPb4Sb4S10
 IMA Status:
Approved IMA
 Locality:
Pribram, Czech Republic.
 Name Origin:
Named for Vladimir Zoubek (1903-), Czech geologist.
Physical Properties:
 Cleavage:
None
 Color:
steel gray.
 Density:
5.15
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Lath - Shaped like a small, thin plaster lath, tabular (rectangular) in shape.,
 Hardness:
3.5-4 - Copper Penny-Flourite
 Luster:
Metallic
 Streak:
black
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