Nekrasovite

See Nekrasov Cossacks for another meaning Nekrasovite is a rare copper vanadium sulfosalt mineral with formula Cu26V2(Sn,As,Sb)6S32. It crystallizes in the isometric system and occurs as small grains in ore aggregates. It is a brown opaque metallic mineral with Mohs hardness of 4.5 and a specific gravity of 4.62.
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General Information:
 Chemical Formula:
Cu13V(Sn,As,Sb)3S16
 IMA Status:
Approved IMA
Physical Properties:
 Color:
reddish brown.
 Density:
4.62
 Diaphaniety:
Opaque
 Hardness:
4.5-5
 Luster:
Metallic
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