Chromite and Other Minerals of Odisha

Chromite - The Strategic Mineral

Odisha holds a virtual monopoly on India’s chromite resources, accounting for approximately 95 per cent of the country’s reserves and nearly all of its production. Chromite (FeCr2O4), the only commercially significant ore of chromium, occurs in the ultramafic rocks of the Archaean Iron Ore Group in a belt stretching approximately 25 kilometres along the Sukinda Valley in Jajpur district and a smaller belt in the Boula-Nausahi area of Keonjhar district. The Sukinda chromite deposits are considered one of the best in the world in terms of grade, with chromium oxide (Cr2O3) content ranging from 40 to 55 per cent, and ore bodies extending to depths of over 300 metres with remarkable continuity. The deposits are principally of the stratiform type, occurring as seams and lenses within serpentinised dunite and peridotite host rocks.

The Sukinda chromite belt, with estimated reserves exceeding 200 million tonnes, is mined by both public sector (Orissa Mining Corporation) and private companies (Tata Steel, Jindal Stainless, IMFA Group, and others) through open-cast operations. The chrome ore is used in three main channels: manufacturing ferrochrome for stainless steel production (the largest consumer), refractory applications (lining for high-temperature furnaces), and the chemical industry (production of chromium compounds used in pigments, tanning, and metal plating). Odisha hosts several ferrochrome plants in the Jajpur-Dhenkanal corridor, including those of Tata Steel, IMFA, and Jindal Stainless, making the state the primary source of ferrochrome for the Indian stainless steel industry and a significant exporter.

The Sukinda Environmental Crisis

The Sukinda chromite mining belt is also one of India’s most severely polluted environments. The open-cast mining and the dumping of overburden have exposed chromite-bearing rocks to accelerated weathering. Rainwater percolating through the overburden dumps and the mine pits dissolves hexavalent chromium (Cr6+), a highly toxic and carcinogenic form, which then enters the groundwater and surface streams, particularly the Damsala and Brahmani tributaries. The concentration of hexavalent chromium in the mine water and nearby water bodies has been recorded at levels far exceeding permissible limits, with devastating consequences for human health (respiratory diseases, skin lesions, gastrointestinal cancers) and aquatic life. The Blacksmith Institute (now Pure Earth) listed Sukinda as one of the world’s most polluted places. Remediation efforts, including the establishment of a common effluent treatment plant, revegetation of overburden dumps, and installation of chromium recovery plants, are underway but have been insufficient to reverse decades of contamination.

Limestone and Dolomite

Limestone is an essential mineral for the cement industry and for the iron and steel industry (used as a flux in blast furnaces). In Odisha, cement-grade limestone occurs in Sundargarh (Biramitrapur and Hatibari areas), Bargarh, and the Nuapada-Kalahandi belt. The Biramitrapur area in Sundargarh district hosts the largest limestone deposits in the state, with reserves estimated at over 1,200 million tonnes. The cement industry in Odisha, concentrated in Sundargarh (ACC, OCL) and Jharsuguda districts, is directly based on these deposits. Dolomite, a calcium-magnesium carbonate rock used mainly as a refractory material and in blast furnaces, is found in association with limestone in Sundargarh district. The state’s dolomite reserves are estimated at about 400 million tonnes.

Graphite, Gemstones, and Other Minerals

Odisha possesses notable deposits of graphite, a critical mineral increasingly in demand for lithium-ion battery anodes. The graphite deposits occur in the Eastern Ghats khondalite belt of Koraput, Rayagada, and Bolangir districts, where graphite schists and graphite-bearing pegmatites are common. The total graphite reserves are estimated at about 15 million tonnes, representing roughly 10 per cent of India’s resources. Gemstones are another speciality of Odisha, particularly the famous ‘pigeon blood’ rubies from the Kalahandi district, sapphires, garnets, and beryl from the Eastern Ghats, and the unique ‘Boudh garnet’ formation. The gemstone deposits have been known and mined for centuries, with traditional lapidary skills concentrated in a few coastal towns.

Chinaclay (kaolin) occurs in Mayurbhanj and Keonjhar districts and supports a small ceramics and refractory industry. Silica sand (quartzite) of high purity for the glass and foundry industries occurs in Puri, Ganjam, and Jagatsinghpur districts. Dimension stones include black granite (gabbro and norite varieties) from Keonjhar and Sundargarh, and multi-coloured granites from various Eastern Ghats locations, which are quarried and exported. Pyrophyllite deposits in Keonjhar support the refractory industry. Nickel, occurring as nickeliferous laterite over ultramafic rocks in the Sukinda area, represents a largely untapped resource — India’s only known significant nickel deposit — with estimated reserves of about 200 million tonnes of ore. The mineral diversity of Odisha is truly remarkable, and the state’s geological endowment will continue to drive its industrial economy for the foreseeable future, even as the emphasis shifts from mere extraction to value addition and sustainable development.