Kamacite

Kamacite is a mineral. It is an alloy of iron and nickel, usually in the proportions of 90:10 to 95:5 although impurities such as cobalt or carbon may be present. On the surface of Earth, it occurs naturally only in meteorites. It has a metallic lustre, is grey and has no clear cleavage although the structure is isometric-hexoctahedral. Its density is around 8 g/cm³ and its hardness is 4 on the Mohs scale. It is also sometimes called balkeneisen.
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General Information:
 Chemical Formula:
alpha-(Fe,Ni)
 Composition:
(Molecular Weight = 56.13 gm)
Iron 89.54 % Fe
Nickel 10.46 % Ni
 Empirical Formula:
Fe0+0.9Ni0.1
Physical Properties:
 Cleavage:
[???] Indistinct
 Color:
iron black or steel gray.
 Density:
7.9
 Diaphaniety:
Opaque
 Hardness:
4 - Fluorite
 Luster:
Metallic
 Streak:
gray
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KAMACITE. CAMACITE