Chromite

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Chromite, only ore mineral of chromium, consisting of ferrous chromite and belonging to the spinel group. It crystallizes in the isometric system (see Crystal) and has a hardness of 5.5 and a specific gravity, or relative density, of 4.1 to 4.8. It is found in irregular brownish-black or black grains or octahedral crystals. Chromite is one of the first minerals to crystallize from magma. It occurs principally in rocks containing various amounts of ferromagnetic minerals. It also occurs in the minerals serpentine and peridotite, as well as in glacial and alluvian deposits. Large deposits of chromite are found in Kazakhstan, Turkey, and Zimbabwe, and also in Austria, Bosnia and Herzegovina, Serbia and Montenegro (formerly the Federal Republic of Yugoslavia), and the Former Yugoslav Republic of Macedonia.

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