Gamma ray source
Permanet magnets
Catalytic conversor of combustion gases

Cobalt and its compounds have several applications. They are used both in laboratory and industrial environment and catalysts; e.g., cobalt molybdena is a catalyst largely used in the oil industry in the oil reforming process.

The well known 60Co is the most used radioactive isotope of this element. It is nowadays the most common source of radiation. It is used in the cold sterilization of food in the USA, Australia, England, France and Russia.

Beside these applications, cobalt compounds are used in ceramics, glaziery, smalt and enamels, in the production and several alloys, special steels, in agriculture salts production and in cobalt plating. The compound used in the production of smalts is the Co3O4, used for example in enameling over iron and steel. In ceramics and paintings, these compounds are particularly useful for preparing pigments.

The cobalt compound are also used in the preparation of "invisible ink" made of a roseous solution of cobalt chloride, which turns into a blue visible ink when heated. This compound is also used in some hygrometers. It turns to blue and pink by action of the atmospheric humidity.