Allactite

General Information:
 Chemical Formula:
Mn7(AsO4)2(OH)8
 Composition:
(Molecular Weight = 798.46 gm)
Manganese 48.16 % Mn
Arsenic 18.77 % As
Hydrogen 1.01 % H 
Oxygen 32.06 % O 
 Empirical Formula:
Mn2+7(AsO4)2(OH)8
 IMA Status:
Accepted IMA 1973
 Locality:
TL: Sweden, Nordmark, Moss mn
Physical Properties:
 Cleavage:
[???] Good
 Color:
brown red, greenish brown, purple red, or pink.
 Density:
3.83
 Diaphaniety:
Translucent
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Vitreous - Greasy
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