Abswurmbachite

Abswurmbachite (or Abswurmbachit or Abswurmbachita or IMA1990-007) (Cu,Mn2+)Mn3+6[O8|SiO4] is a mineral of copper, manganese, oxygen, and silicon. It is named after Irmgard Abs-Wurmbach, a German mineralogist. Its Mohs scale rating is 6.5.
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General Information:
 Chemical Formula:
Cu++Mn+++6SiO12
 Composition:
(Molecular Weight = 613.25 gm)
Manganese 53.75 % Mn
Silicon 4.58 % Si
Copper 10.36 % Cu
Oxygen 31.31 % O 
 Empirical Formula:
CuMn3+6SiO12
 IMA Status:
Approved IMA 1990
 Locality:
TL: Greece, Milli, Avia and Andros Island
Physical Properties:
 Cleavage:
None
 Color:
black or dark brown.
 Density:
4.96
 Diaphaniety:
Opaque
 Hardness:
6.5 - Pyrite
 Luster:
Metallic
 Streak:
brownish black
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