heterogenite

Heterogenite is a mineral species consisting of cobalt hydroxide with the chemical formula CoO(OH). It is a secondary mineral, typically formed by the oxidation of primary cobalt minerals in the upper portions of ore deposits. The mineral is known for its black to dark gray color and a dull to metallic luster. It commonly occurs in massive, earthy, or botryoidal forms, and is often found intimately associated with other cobalt minerals such as heterogenite and erythrite. Heterogenite is a relatively soft mineral, with a hardness of around 4.5 on the Mohs scale, and has a specific gravity of approximately 3.2. It is insoluble in water but can be attacked by acids. The mineral is an important ore of cobalt, a metal with numerous industrial applications including the production of alloys, batteries, and pigments. Deposits containing heterogenite are found in various locations worldwide, often in arid or semi-arid environments where oxidative weathering processes are prevalent. Its identification can be challenging due to its similarity in appearance to other black oxide and hydroxide minerals.

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