Co • Atomic number 27
Cobalt
Cobalt is a hard, silvery-grey transition metal with the chemical symbol Co. It is ferromagnetic and retains useful mechanical properties at high temperatures. Cobalt usually occurs together with nickel and copper ores.
Cobalt is used in high-temperature superalloys, rechargeable batteries, hard metals, catalysts, magnets, pigments and wear-resistant coatings. Its combination of heat resistance, magnetic properties and electrochemical performance makes it important for many technologies.
Most cobalt is recovered as a co-product of copper or nickel mining. Concentrates are leached and refined through several separation stages to remove copper, nickel, iron and other impurities before cobalt metal or salts are produced.
Cobalt dust and some compounds can be harmful through inhalation or prolonged exposure. Controlled handling, ventilation and traceable supply chains are important for occupational, environmental and responsible-sourcing reasons.
The technical assessment of a material always depends on purity, chemical form, particle size, packaging and intended use.