Petrology and Geochemistry of a Recently Discovered Nickeliferous Serpentinite in Sri Lanka

Geological and geochemical investigations of a serpentinized ultramafic body in the south of Sri Lanka have revealed the presence of nickel in the range 0.8-1.9%. Nickel is present in silicate form in the serpentine minerals. The typical tropical climate prevailing has been responsible for the formation of a deep weathering profile conducive to the residual enrichment of nickel. Cobalt, chromium and zinc are also present, though in lesser quantities when compared to nickel. The opaque minerals consisted of magnetite, chromite/picotite and other spinels. The leaching of silica and magnesium had resulted in the formation of chert, agate, chalcedony and carbonate veins respectively.