Ferrisicklerite

General Information:
 Chemical Formula:
Li(Fe+++,Mn++)PO4
 Composition:
(Molecular Weight = 157.53 gm)
Lithium 4.41 % Li
Manganese 8.72 % Mn
Iron 26.59 % Fe
Phosphorus 19.66 % P 
Oxygen 40.63 % O 
 Empirical Formula:
LiFe3+0.75Mn2+0.25(PO4)
Physical Properties:
 Cleavage:
[100] Good
 Color:
yellow brown or dark brown.
 Density:
3.41
 Diaphaniety:
Opaque
 Hardness:
4 - Fluorite
 Luster:
Earthy (Dull)
 Streak:
light brown
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