Yttrium

Yttrium is a soft, silvery transition metal also counted among the rare-earth elements because its chemistry closely resembles that of the lanthanides. It occurs combined with other elements in minerals such as xenotime and in rare-earth-rich clays, rather than as pure metal. Producers separate its compounds from those of other rare earths in solution; the metal can then be obtained by reacting yttrium fluoride with a calcium–magnesium alloy. Some of yttrium's most striking uses involve light. Yttrium aluminum garnet crystals containing small amounts of cerium help produce white light in LEDs. With neodymium added instead, these synthetic crystals are used in lasers powerful enough to cut metal.