Ordonezite

Ordóñezite is a tetragonal pyramidal crystal and is found in Rhyolite fractures. The Santín mine which is located about eight kilometres from Santa Catarina, Guanajuato, Mexico is a main producer of Ordóñezite. Another is El Antimonio, 27 kilometres southwest of Agua Prieta, Sonora, Mexico.
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General Information:
 Chemical Formula:
ZnSb2O6
 Composition:
(Molecular Weight = 404.89 gm)
Zinc 16.15 % Zn
Antimony 60.14 % Sb
Oxygen 23.71 % O 
 Empirical Formula:
ZnSb2O6
Physical Properties:
 Cleavage:
None
 Color:
colorless, yellow green, light brown, dark brown, or olive green.
 Density:
6.635
 Diaphaniety:
Transparent
 Hardness:
6.5 - Pyrite
 Luster:
Adamantine
 Streak:
greenish gray
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