Maghagendorfite

General Information:
 Chemical Formula:
NaMgMn(Fe++,Fe+++)2(PO4)3
 Composition:
(Molecular Weight = 498.84 gm)
Sodium 4.61 % Na
Magnesium 4.87 % Mg
Manganese 11.01 % Mn
Iron 22.39 % Fe
Phosphorus 18.63 % P 
Oxygen 38.49 % O 
 Empirical Formula:
NaMgMn2+Fe2+1.5Fe3+0.5(PO4)3
 IMA Status:
Approved IMA 1979
Physical Properties:
 Cleavage:
[???] Good
 Color:
greenish black.
 Hardness:
3.5 - Copper Penny
 Streak:
gray green
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