Retgersite

General Information:
 Chemical Formula:
NiSO4·6(H2O)
 Composition:
(Molecular Weight = 262.85 gm)
Nickel 22.33 % Ni
Hydrogen 4.60 % H 
Sulfur 12.20 % S 
Oxygen 60.87 % O 
 Empirical Formula:
Ni(SO4)·6(H2O)
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
dark green.
 Density:
2.07
 Hardness:
2.5 - Finger Nail
 Luster:
Vitreous (Glassy)
 Streak:
greenish white
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