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It was discovered by Lieutenant Carl Axel Arrhenius in 1787 at a quarry in the village of Ytterby, Sweden.Arrhenius's "ytterbite" reached Johan Gadolin, a Royal Academy of Turku professor, and his analysis yielded an unknown oxide (earth) that he called yttria.

Wir bieten den europäischen Singles die online Kontaktanzeigen Frauen aus Russland und Osteuropa. Despite their name, rare-earth elements are – with the exception of the radioactive promethium – relatively plentiful in Earth's crust, with cerium being the 25th most abundant element at 68 parts per million, more abundant than copper.They are not especially rare, but they tend to occur together in nature and are difficult to separate from one another.However, because of their geochemical properties, rare-earth elements are typically dispersed and not often found concentrated as rare-earth minerals in economically exploitable ore deposits.The first such mineral discovered (1787) was gadolinite, a mineral composed of cerium, yttrium, iron, silicon, and other elements.

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