Gebhardite

General Information:
 Chemical Formula:
Pb8(As+++2O5)2OCl6
 Composition:
(Molecular Weight = 2,346.00 gm)
Arsenic 12.77 % As
Lead 70.66 % Pb
Chlorine 9.07 % Cl
Oxygen 7.50 % O 
 Empirical Formula:
Pb8As4O11Cl6
Physical Properties:
 Cleavage:
[001] Perfect, [010] Good
 Color:
light brown.
 Density:
6
 Diaphaniety:
Transparent
 Hardness:
3 - Calcite
 Luster:
Adamantine
 Streak:
white
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