Terbium was discovered by Carl Gustaf Mosander (Sweden) in 1843. Named after Ytterby, a village in Sweden. It is soft, ductile, silvery-grey, rare earth metal. Oxidizes slowly in air. Reacts with cold water. Terbium is found with other rare earths in monazite sand. Other sources are xenotime and euxenite, both of which are oxide mixtures that can contain up to 1 % terbium. It is used in modest amounts in special lasers and solid-state devices.
Generalic, Eni. "Terbium." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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