Arseniopleite

General Information:
 Chemical Formula:
NaCaMn++3(AsO4)3
 Composition:
(Molecular Weight = 644.64 gm)
Sodium 3.57 % Na
Calcium 6.22 % Ca
Manganese 25.57 % Mn
Arsenic 34.87 % As
Oxygen 29.78 % O 
 Empirical Formula:
NaCaMn2+3(AsO4)3
 Environment:
Mn-rich member of a series with caryinite.
 Locality:
Sjo Mine, Grythytte Parish, Orebro, Sweden.
 Name Origin:
Named from the Latin for the element As, and Greek for 'more' because it adds to the number of related minerals already described.
Physical Properties:
 Cleavage:
[???] Good
 Color:
cherry or reddish brown.
 Density:
4.22 - 4.29, Average = 4.25
 Diaphaniety:
Opaque
 Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., ,
 Hardness:
3.5 - Copper Penny
 Luster:
Greasy (Oily)
 Streak:
yellowish brown
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