A Short Geological Review of the Bushveld Complex

At present most of the worldwide supply of platinum and palladium and the associated elements is obtained from mines within four major layered igneous intrusions. These are the Bushveld Complex in South Africa, the Stillwater Complex in the U.S.A., the Great Dyke in Zimbabwe, and the Noril’sk/Talnakh Complexes in Russia (1). These layered intrusions consist of rocks which cooled slowly from molten magma, deep within the earth. Silicate minerals in fixed proportions crystallised and aggregated to form the final igneous rocks. The composition of the minerals changed with the slow drop in temperature in the magma brought about by cooling. The first silicate minerals which crystallised and settled out are rich in magnesium and iron (the ‘mafic’ parts of the