Heazlewoodite

Heazlewoodite, Ni3S2, is a rare sulfur-poor nickel sulfide mineral found in serpentinitised dunite. It occurs as disseminations and masses of opaque, metallic light bronze to brassy yellow grains which crystallise in the trigonal crystal system. It has a hardness of 4 and a specific gravity of 5.82.
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General Information:
 Chemical Formula:
Ni3S2
 Composition:
(Molecular Weight = 240.20 gm)
Nickel 73.30 % Ni
Sulfur 26.70 % S 
 Empirical Formula:
Ni3S2
Physical Properties:
 Cleavage:
None
 Color:
light bronze or brass yellow.
 Density:
5.82
 Diaphaniety:
Opaque
 Hardness:
4 - Fluorite
 Luster:
Metallic
 Streak:
light bronze
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