One of the most important applications of cerium is in the production of cerium mischmetal. This metal alloy, which is used in steel production, consists of various metals and rare earths such as neodymium, praseodymium, terbium and yttrium. In addition, the industry requires cerium in the form of cerium oxides for the coating of car exhaust catalytic converters. The metal is also used as a polishing agent for optical glass, as a UV absorber, e.g. in windscreens, or for coloring and decoloring glass.