Nickel (Ni) is hard, silver white metal that has numerous physical and chemical properties including strength, corrosion resistance, high ductility, good thermal and electrical conductivity, magnetic characteristics, and catalytic properties. Nickel’s primary use is in the manufacture of stainless steel, steel alloys and superalloys, which have a major role in the development of the chemical and aerospace industries. Nickel is also used in batteries and fuel cells, and as a catalyst in the hydrogenation of fats and oils.

Economic concentrations of nickel can be found in two differing geological environments, as a sulphide ore and as a lateritic nickel ore. The main economic sulphide nickel mineral is pentlandite (Fe, Ni)9S8, which occurs with pyrrhotite (FenSn+1), pyrite (FeS), and chalcopyrite (CuFeS2) in lodes in mafic and ultramafic igneous rocks. The major lateritic nickel mineral is garnierite ((Ni, Mg)SiO3.nH2O) and nickeliferous limonite (nickel mixed with hydrated iron oxide). The nickel grade of sulphide ore typically ranges from 1-4 % nickel, and that of lateritic ore from 1-2 % nickel. Australia, Russia and Canada are the world’s major producers of nickel.

Cobalt (Co) is not found as a native element on earth. It is a brittle, hard, transition metal with magnetic properties similar to those of iron. It is mainly used as an alloy with iron, nickel and other metals to produce corrosion and wear resistant products used in high temperature applications such as jet engines and gas turbine engines. Cobalt based alloys are also used in high abrasion resistant steels. Cobalt oxide is an important additive in paint, glass and ceramics, which gives them a brilliant and permanent blue colour.

Cobalt is produced as a by-product of nickel and copper mining activities. The main economic ore mineral of cobalt is cobaltite (CoAsS), erythrite CO3(AsO4)2.8H2O), glaucodot ((Co,Fe)AsS), and skutterudite (CoAs3). The DRC, Zambia, Russia and Australia are the world’s major producers of cobalt.