NÉPOUITE
Class : Silicates
Subclass : Phyllosilicates
Crystal system : Orthorhombic
Chemistry : Ni3Si2O5(OH)4
Rarity : Quite common
Népouite is a rare nickel silicate belonging to the serpentine group ; it forms a continuous series with lizardite. It is a secondary mineral formed by alteration of peridotites and dunites rich in nickel which enters into the constitution of "garnierites", these nickel-bearing silicates exploited as nickel ore. It was named in reference to its place of discovery : the Reis II mine in Népoui (New Caledonia). Népouite is a light to dark green mineral, the intensity of the green depending on the nickel content, a metal that iron and magnesium can replace in significant proportions.
Main photo : Népouite from Népoui Mine, New Caledonia © Lee Johnson
Népouite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 2 to 2.5
Density : 3.24
Fracture : Irregular
Streak : White-green
TP : Translucent to opaque
RI : 1.576 to 1.650
Birefringence : 0.027
Optical character : Biaxial -
Pleochroism : Low
Fluorescence : None
Solubility : -
Magnetism : NoneRadioactivity : None