Fedorovskite

General Information:
 Chemical Formula:
Ca2(Mg,Mn)2B4O7(OH)6
 Composition:
(Molecular Weight = 401.36 gm)
Calcium 19.97 % Ca
Magnesium 9.08 % Mg
Manganese 6.84 % Mn
Boron 10.77 % B 
Hydrogen 1.51 % H 
Oxygen 51.82 % O 
 Empirical Formula:
Ca2Mg1.5Mn2+0.5B4O7(OH)6
 IMA Status:
Approved IMA 1976
Physical Properties:
 Cleavage:
[100] Perfect
 Color:
brown.
 Density:
2.65
 Diaphaniety:
Transparent
 Hardness:
4.5 - Between Fluorite and Apatite
 Streak:
brownish
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