Zemannite

General Information:
 Chemical Formula:
Mg0.5[Zn++Fe+++(TeO3)3]·4.5(H2O)
 Composition:
(Molecular Weight = 741.25 gm)
Magnesium 1.64 % Mg
Zinc 8.82 % Zn
Iron 7.53 % Fe
Tellurium 51.64 % Te
Hydrogen 1.22 % H 
Oxygen 29.14 % O 
 Empirical Formula:
Mg0.5ZnFe3+(TeO3)3·4.5(H2O)
 IMA Status:
Approved IMA 1969
Physical Properties:
 Cleavage:
[???] Good
 Color:
light brown or dark brown.
 Density:
4.05
 Luster:
Adamantine
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