Andremeyerite

General Information:
 Chemical Formula:
BaFe(Fe++,Mn,Mg)Si2O7
 Composition:
(Molecular Weight = 413.76 gm)
Barium 33.19 % Ba
Magnesium 0.59 % Mg
Manganese 3.98 % Mn
Iron 21.60 % Fe
Silicon 13.58 % Si
Oxygen 27.07 % O 
 Empirical Formula:
BaFe2+1.6Mn2+0.3Mg0.1Si2O7
 IMA Status:
Approved IMA 1972
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
emerald green.
 Density:
4.15
 Hardness:
5.5 - Knife Blade
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