General Information:
Chemical Formula:
(Fe++,Mn)Fe+++4(PO4)3(OH)5
Composition:
(Molecular Weight = 648.96 gm)
Manganese 2.12 % Mn
Iron 40.88 % Fe
Phosphorus 14.32 % P
Hydrogen 0.78 % H
Oxygen 41.91 % O
Empirical Formula:
Fe2+0.75Mn2+0.25Fe3+4(PO4)3(OH)5
Physical Properties:
Cleavage:
[100] Perfect, [010] Distinct, [001] Distinct
Color:
green, dark olive green, black, brownish green, or reddish brown.
Density:
3.3 - 3.49, Average = 3.39
Diaphaniety:
Subtranslucent
Hardness:
4.5 - Between Fluorite and Apatite
Luster:
Vitreous - Dull
Streak:
greenish gray
More details...