Akrochordite

General Information:
 Chemical Formula:
Mn4Mg(AsO4)2(OH)4·4(H2O)
 Composition:
(Molecular Weight = 661.99 gm)
Magnesium 3.67 % Mg
Manganese 33.20 % Mn
Arsenic 22.64 % As
Hydrogen 1.83 % H 
Oxygen 38.67 % O 
 Empirical Formula:
Mn4+4Mg(AsO4)2(OH)4·4(H2O)
 Locality:
TL: Sweden, V„rmland, Filipstad, L†ngban mn
Physical Properties:
 Cleavage:
[???] Good
 Color:
reddish brown.
 Density:
3.19 - 3.26, Average = 3.22
 Diaphaniety:
Translucent
 Hardness:
3.5 - Copper Penny
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