Californium is a chemical element. It is a radioactive metal. It has the chemical symbol Cf. It has the atomic number 98. Californium is a transuranium element. Californium does not have many uses. It was discovered by bombarding a curium target with alpha particles (helium ions). Californium is named after the US State of California, where it was discovered, in the University of Berkeley.
Californium is produced in nuclear reactors and particle accelerators. There are 20 known isotopes. The most stable is californium-251, which has a half-life of 898 years. This short half-life means the element is not found in the Earth's crust. Californium-252, whose half-life is 2.645 years, is the most common isotope used.
Compounds of californium are mostly of californium(III), which can take part in three chemical bonds. Californium can be used to help start up nuclear reactors, and is used as a source of neutrons. It can be used in making higher mass elements. Ununoctium was synthesized by bombarding californium-249 atoms with calcium-48 ions.
When californium is used, workers must be protected from the element's ability to disrupt the formation of red blood cells.