cobalt

/ˌkoʊˈbɔlt/

/ˈkʌʊbɔlt/

Other forms: cobalts

Cobalt is a silvery-gray metal. It's also the name of a deep blue pigment that's made from cobalt.

Cobalt, mined from the earth's crust along with copper and nickel, has a shiny appearance with a slightly bluish tint. Chemically combining cobalt with aluminum oxide results in the blue pigment that's been familiar to artists for centuries. Cobalt blue is the blue in very old Chinese blue-and-white porcelain, and it features in paintings by Monet and van Gogh. Cobalt is from the German kobold, "household goblin," a nickname miners gave arsenic-laced ore that made them sick.

Definitions of cobalt

1. noun

   a hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition
   synonyms: Co, atomic number 27

   types:

   cobalt 60

   a radioactive isotope of cobalt with mass number 60; a source of exceptionally intense gamma rays; used in radiation therapy

   type of:

   metal, metallic element

   any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.