Namansilite

General Information:
 Chemical Formula:
NaMn+++(Si2O6)
 Composition:
(Molecular Weight = 230.10 gm)
Sodium 9.99 % Na
Manganese 23.88 % Mn
Silicon 24.41 % Si
Oxygen 41.72 % O 
 Empirical Formula:
NaMn3+Si2O6
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[???] Perfect
 Color:
brownish red or violet red.
 Density:
3.6
 Diaphaniety:
Transparent
 Hardness:
6-7 - Orthoclase-Quartz
 Luster:
Vitreous - Pearly
 Streak:
brown red
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