Cobaltite

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Cobaltite, mineral, a compound of cobalt, arsenic, and sulfur. It occurs in isometric crystals resembling those of pyrite. It is silver white to red in color and has a metallic luster. The specific gravity of cobaltite is between 6 and 6.4, and the hardness is 5.5. Cobaltite occurs in high-temperature vein deposits or in disseminations in rocks associated with nickel and other cobalt minerals. It is mined as an important ore of cobalt. Large deposits are found in Sweden, Norway, Myanmar (formerly known as Burma), Australia, and Ontario in Canada.

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