Cobalt is a hard, lustrous, grey metal, a chemical element with symbol Co and atomic number 27. Cobalt-based colors and pigments have been used since ancient times for jewellery and paints, and miners have long used the name kobold ore for some minerals.
Cobalt is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Smalte (cobalt silicate glass) and cobalt blue (cobalt(II) aluminate, CoAl2O4) gives a distinctive deep blue color to glass, ceramics, inks, paints, and varnishes. Cobalt-60 is a commercially important radioisotope, used as a tracer and in the production of gamma rays.
Cobalt is an essential trace element for all animal organisms as the active center of coenzymes called cobalamins. These include vitamin B-12 which is essential for mammals. Cobalt is also an active nutrient for bacteria, algae, and fungi.
Cobalt is a ferromagnetic metal with a specific gravity of 8.9 (20°C). Compounds of cobalt are common. Small amounts of it are found in most rocks, soil, plants, and animals. The Curie temperature is 1115 °C, and the magnetic moment is 1.6–1.7 Bohr magnetons per atom. In nature, it is frequently associated with nickel, and both are characteristic minor components of meteoric iron. Cobalt has a relative permeability two thirds that of iron. Metallic cobalt occurs as two crystallographic structures: hcp and fcc.
59-Cobalt is the only stable cobalt isotope and the only isotope to exist in nature. 22 radioisotopes have been characterized with the most stable being 60-Co with a half-life of 5.2714 years, 57-Co with a half-life of 271.79 days, 56-Co with a half-life of 77.27 days, and 58-Co with a half-life of 70.86 days. All of the remaining radioactive isotopes have half-lives that are less than 18 hours, and the majority of these are less than 1 second. This element also has 4 meta states, all of which have half-lives less than 15 minutes.
The base value of each unit of ranges between 5 and 15Ð per unit, with up to 3 units being found at any one time.
Presence on Mars: Common
|Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6|
|Group 1|||Aluminum | Arsenic | Beryllium | Boron | Calcium | Cantite | Carbon | Chlorine | Chromium | Cobalt | Copper | Flourine | Helium| | Hydrogen | Iron | Lithium | Magnesium | Manganese | Nickel | Oxygen | Phosphorus | Plesium | Potassium | Silicon | Sodium||