Alamosite

Alamosite (Pb12[Si12O36]) is a mineral found in Mexico.
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General Information:
 Chemical Formula:
PbSiO3
 Composition:
(Molecular Weight = 283.28 gm)
Silicon 9.91 % Si
Lead 73.14 % Pb
Oxygen 16.94 % O 
 Empirical Formula:
Pb(SiO3)
 Locality:
TL: Russia, Tyuya-muyun, Alai Mts, Ferghana
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
colorless or white.
 Density:
6.49
 Diaphaniety:
Transparent to Translucent
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Adamantine
 Streak:
white
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