General Information:
Chemical Formula:
(Mn,Mg)13(Al,Fe+++)4Sb+++++2Si2O28
Physical Properties:
Cleavage:
[001] Perfect
Color:
black or red.
Density:
4.56
Diaphaniety:
Translucent to Opaque
Hardness:
5.5 - Knife Blade
Luster:
Metallic
Streak:
red brown
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