Applications
Some Erbium is added to alloys with metals such Vanadium because it lowers their
hardness, making them more workable. Due to its adsorption of infrared light,
Erbium is added to the glass of special safety spectacles for workers, such as
welders and glass-blowers. It is used as a photographic filter as well, and to
dope optical fibers at regular intervals to amplify signals. Finally, due to its
pink colour, Erbium is sometimes used as a glass and porcelain enamel glaze
colorant.
Erbium in the environment
Erbium is never found as a free element in nature. It is found in minerals that
include all the rare-earth elements. Erbium is one of the more abundant
rare-earth elements. The main mining areas are China and US. The most important
ores are monazite and bastanite, were it is present in extrable amounts. Better
suorces of the element are xenotime and euxenite. World production of Erbium is
500 tonnes per year.
Health effects of Erbium
Erbium has no biological role even if it has been noted that it stimulates
metabolism. It is difficult to determine the amount of herbium present in the
human body. The levels are highest in bones, with smaller amounts being present
in the liver and kidneys.
Environmental effects of erbium
Holmium poses no Environmental therat to plants and animals.