As we have already seen, many elements were discovered in the Swedish village Ytterby. The element erbium was one among them, and was discovered in 1843. It was the Swedish chemist Carl Gustaf Mosander who discovered the element. Mosander was working with a sample of what was thought to be the single metal oxide yttria, derived from the mineral gadolinite. He extracted three segments from it and called them yttria, erbia and terbia. As might be expected considering the similarities between their names and properties, scientists soon confused erbia and terbia. Mosander’s terbia became known as erbia after 1860, and the earlier known erbia was renamed terbia after 1877!
It is difficult to find natural erbium independently on earth as it is always found in chemical compounds. Erbium has a special ability to absorb harmful infra-red rays. Therefore, the element is used in the glass of safety goggles for welders.
Erbium occurs in a variety of minerals, including gadolinite, euxenite, xenotime, fergusonite, polycrase and blomstrandine.
The atomic number of erbium is 68, and its symbol is Er.
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