In order to investigate the mineralizations of chromite and platinum group elements in Precambrian ultramafic rocks of Goias State, Central Brazil, two complexes have been selected for detailed mineralogical and chemical studies. These are the Morro Feio serpentinized massif, which has been tectonically emplaced into Middle Proterozoic metasediments of the Uruaçu fold belt, and the Niquelandia layered mafic-ultramafic complex, intrusive into the Archean granite-gneiss basement; both have lateritic covers developed under tropical weathering conditions. The Morro Feio massif is a zoned ultramafic body, with a discontinuous external zone. The internal nucleus of the body consists of an antigorite-serpentinite zone where most of the chromite pods occur.