Taikanite

General Information:
 Chemical Formula:
(Ba,Sr)2Mn+++2Si4O12
 Composition:
(Molecular Weight = 664.01 gm)
Barium 31.02 % Ba
Strontium 6.60 % Sr
Manganese 16.55 % Mn
Silicon 16.92 % Si
Oxygen 28.91 % O 
 Empirical Formula:
Ba1.5Sr0.5Mn3+2Si4O12
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
greenish black.
 Density:
4.72
 Diaphaniety:
Translucent to Opaque
 Hardness:
6-7 - Orthoclase-Quartz
 Luster:
Vitreous - Greasy
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