Dixenite

General Information:
 Chemical Formula:
Cu+Mn++14Fe+++(As+++O3)5(SiO4)2(As+++++O4)(OH)6
 Composition:
(Molecular Weight = 1,928.25 gm)
Manganese 39.89 % Mn
Iron 2.90 % Fe
Copper 3.30 % Cu
Silicon 2.91 % Si
Arsenic 23.31 % As
Hydrogen 0.31 % H 
Oxygen 27.38 % O 
 Empirical Formula:
CuMn2+14Fe3+(AsO3)5(SiO4)2(AsO4)(OH)6
 Locality:
Langbanshyttan, Vermland, Sweden.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
bronze or black.
 Density:
4.2
 Diaphaniety:
Translucent to subtranslucent to opaque
 Habits:
Foliated - Two dimensional platy forms., ,
 Hardness:
3-4 - Calcite-Fluorite
 Luster:
Vitreous (Glassy)
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