Zaratite

Zaratite is a bright emerald green nickel carbonate mineral with formula Ni3CO3(OH)4·4H2O. Zaratite crystallizes in the isometric crystal system as massive to mammillary encrustations and vein fillings. It has a specific gravity of 2.6 and a Mohs hardness of 3 to 3.5. It has no cleavage and has a brittle to conchoidal fracture. The luster is vitreous to greasy.
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(n.)
A hydrous carbonate of nickel occurring as an emerald-green incrustation on chromite; -- called also emerald nickel.
  

General Information:
 Chemical Formula:
Ni3(CO3)(OH)4·4(H2O)
 Composition:
(Molecular Weight = 325.15 gm)
Nickel 54.15 % Ni
Hydrogen 2.79 % H 
Carbon 3.69 % C 
Oxygen 39.37 % O 
 Empirical Formula:
Ni3(CO3)(OH)·4(H2O)
 Locality:
Cape Ortegal, Galicia, Spain. Broken Hill, New South Wales, Australia.
 Name Origin:
Named after Antonio Gil y Zarate (1793-1861), Spanish diplomat, general director of public education, and counselor of state.
Physical Properties:
 Cleavage:
None
 Color:
emerald green.
 Density:
2.6
 Diaphaniety:
Translucent
 Habits:
Mammillary - Larger "breast-like" rounded forms resembling botryoidal (e.g. malachite)., Encrustations - Forms crust-like aggregates on matrix., Massive - Uniformly indistinguishable crystals forming large masses.
 Hardness:
3-3.5 - Calcite-Copper Penny
 Luminescence:
None.
 Luster:
Vitreous - Greasy
 Streak:
light green
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ZARATITE [MINERALE]