Spherocobaltite is a cobalt carbonate mineral with chemical composition CoCO3. It belongs to the calcite group of minerals, a group of related carbonates that are isomorphous with one another. They are similar in many physical properties and may partially or fully replace one another, forming a solid solution series.
Spherocobaltite was first described in 1877 for an occurrence within cobalt and nickel veins in the St. Daniel Mine of the Schneeberg District, Erzgebirge, Saxony, Germany. The name is from the Greek “sphaira”, sphere, and cobalt.
Pure Spherocobaltite is quite uncommon as the cobalt is usually mixed with calcium. This leads to confusion with the term Cobaltocalcite. Cobaltocalcite refers to an intermediary mineral between Calcite and Spherocobaltite in a solid solution series.