The notion of "bewitched" minerals stems from cobaltite and other cobalt ores withstanding the smelting methods of the medieval period, often producing foul-smelling, poisonous fumes in the process.

It occurs in association with magnetite, sphalerite, chalcopyrite, skutterudite, allanite, zoisite, scapolite, titanite, and calcite along with numerous other Co–Ni sulfides and arsenides.

[3] It is found chiefly in Sweden, Norway, Germany, Cornwall, England, Canada, La Cobaltera, Chile, Australia, the Democratic Republic of the Congo, and Morocco.

[3][7][5] Crystals have also been found at Khetri in Rajasthan, and under the name sehta the mineral was used by Indian jewellers for producing a blue enamel on gold and silver ornaments.

[citation needed] A variety containing much iron replacing cobalt, and known as ferrocobaltite (German: Stahlkobalt), was found at Siegen in Westphalia.