Mahnertite

General Information:
 Chemical Formula:
(Na,Ca)Cu++3(AsO4)2Cl·5(H2O)
 Composition:
(Molecular Weight = 621.27 gm)
Sodium 2.78 % Na
Calcium 1.61 % Ca
Copper 30.69 % Cu
Arsenic 24.12 % As
Hydrogen 1.62 % H 
Chlorine 5.71 % Cl
Oxygen 33.48 % O 
 Empirical Formula:
Na0.75Ca0.25Cu3(AsO4)2Cl·5(H2O)
 Environment:
Found in a zone of secondary alteration.
 IMA Status:
Approved IMA
 Locality:
Cap Garonne mine, Var, France.
 Name Origin:
Named after Volker Mahnert (b. 1943), zoologist, director of the Mus‚um d'Histoire Naturelle, Geneva, Switzerland.
Physical Properties:
 Color:
blue or emerald green.
 Density:
3.33
 Diaphaniety:
Translucent
 Hardness:
2-3 - Gypsum-Calcite
 Luster:
Vitreous (Glassy)
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