Chromite, iron magnesium chromium oxide: (Fe, Mg)Cr2O4, is an oxide mineral belonging to the spinel group. Magnesium is always present in variable amounts, also aluminium and iron substitute for chromium.
Chromite is found in peridotite and other layered ultramafic intrusive rocks and also found in metamorphic rocks such as serpentinites. Ore deposits of chromite form as early magmatic differentiates. It is commonly associated with olivine, magnetite, serpentine, and corundum. The vast Bushveld igneous complex of South Africa is a large layered mafic to ultramafic igneous body with some layers consisting of 90% chromite making the rare rock type, chromitite. Chromite is also used as a refractory material.
The only ore of chromium is the mineral chromite. In the western hemisphere, chromite ore is produced only in Brazil and Cuba; By comparison, about 80% of world production of chromite comes from India, Iran, Pakistan, Oman, Zimbabwe, Turkey and Southern Africa. Southern Africa itself produces about half of this.
|CHROMITE RESOURCES IN INDIA|
Chromite deposits associated with Iron Ore Group are most important. Among them two belts namely Sukinda Ultramafic Belt and Nausahi Utramafic Belt of Orissa contain about 97% of total Indian resources of Chromite. The major chromite resources are from Sukinda followed by Baula- Nausahi area of Orissa. Small resources have been established in Karnataka, Maharashtra and Jharkhand. As per UNFC system, total resources of chromite in the country as on 1-4-2005 are estimated at 231 million tones, comprising 66 million tones reserves and 147 million tones remaining resources (69%).
Chromite is mined mostly by opencast method in the country. Underground mines are confined to Byrapur in Karnataka and Boula and Kathpal mines in Orissa.