Definition

Cobalt is a solid, lustrous, grey metal, a chemical component with symbol Co. Although cobalt-based colors and pigments have been used since ancient times for creation of jewelry and paints, and miners have long used the name kobold ore for some minerals, the free metallic cobalt was not set and discovered until 1735 by Georg Brandt.

Properties

Cobalt is a ferromagnetic metal. Pure cobalt is not found in nature, but compounds of cobalt are common. Small amounts of it are found in most rocks, soil, plants, and animals. It is the component of atomic number 27. The Curie temperature is 1115 °C, and the magnetic moment is 1.6–1.7 Bohr magnetons per atom.

World Resources

Application

Cobalt-based superalloys put away most of the created cobalt. The temperature stability of these alloys makes them suitable for use in turbine blades for gas turbines and jet aircraft engines, though nickel-based single crystal alloys surpass them in this regard. Cobalt-based alloys are also corrosion and wear-resistant. Special cobalt-chromium-molybdenum alloys are used for prosthetic parts such as hip and knee replacements.