Cobalt Facts

Cobalt's Basic Information

• Cobalt comes from the German word, kobald, meaning goblin or evil spirit, and the Greek word, cobalos, for mine. Though it can give pottery a brilliant blue color, it is actually a grayish metal. On the periodic table of elements, cobalt is identified by the symbol: Co and the atomic number of 27. It has an atomic weight of 58.933195. It is in group 9, period 4 and d-bloc on the periodic table.

History of Cobalt

• Cobalt has been used to give a deep, blue color to glass and ceramics. It has been found in Egyptian sculpture and Persian jewelry.
  Swedish chemist Georg Brandt discovered cobalt in 1735. He wanted to prove that an unknown element rather than bismuth made glass blue. Cobalt is usually recovered as a byproduct of mining nickel, silver, lead, copper and iron.
  John Livingood and Glenn Seaborg discovered cobalt-60 in 1938. This radioactive isotope was used at Columbia University in the 1950s to establish parity violation in beta decay. Their work was submitted to the journal "The Physical Review" in January 1957.

Cobalt Uses

• Cobalt has been used for centuries as a way to color porcelain, glass, pottery and tile. Some of colors created from cobalt include: cobalt blue, ceruleum, new blue, smalt, cobalt yellow and cobalt green. Cobalt can be used in electroplating to give metals a surface that resists oxidation. It is used in alloys like alnico (used to make powerful magnets) and satellite (used for high-speed and high-temperature cutting tools and dyes). You can also find it in alloys for jet engines, gas turbines, some batteries and steels. Humans also need cobalt because it is a part of Vitamin B12.

Radioactive Cobalt

• Cobalt-60 is a radioactive isotope of cobalt made by exposing cobalt to neutrons in a reactor. It emits gamma rays and is used to treat some cancers. It can also sterilize medical supplies and waste. It can also be used as a medical tracer. It has a half-life of 5.27 years and decays into nickel-60.

Where Cobalt is Found

• Cobalt ore is found in a few mines around the world. In 2005, the Congo supplied 40 percent of cobalt from a copper mine in Katanga province. Other deposits are found in Zaire, Canada and Morocco.