Chromium is never found free in Nature and most ores consist of the mineral chromite. The ideal formula for this ore is (FeO-Cr2O3), containing 68% (Cr2O3) and 32% FeO, but the actual composition of the higher grade ores varies, with also varying amounts of magnesia, alumina and silica.

The main sources of chromite are the former USSR, South Africa, Philipines and Zimbabwe.