Erbium (Irbiəm) is a chemical element in the lanthanide series, with the symbol "Er" and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth. As such, it is a rare earth element which is associated with several other rare elements in the mineral gadolinite from Ytterby in Sweden. Erbium's principal uses involve its pink- colored Er3+ ions, which have optical fluorescent properties particularly useful in certain laser applications. Erbium-doped glasses or crystals can be used as optical amplification media, where erbium (III) ions are optically pumped at around 980 nm or 1480 nm and then radiate light at 1530 nm in stimulated emission. This process results in an unusually mechanically simple laser optical amplifier for signals transmitted by fiber optics. The 1550 nm wavelength is especially important for optical communications because standard single mode optical fibers have minimal loss at this particular wavelength. In addition to optical fiber lasers, a large variety of medical applications (i.e. dermatology, dentistry) utilize erbium ion's 2940 nm emission (see Er:YAG laser), which is highly absorbed in water in tissues, making its effect very superficial. Such shallow tissue deposition of laser energy is helpful in laser surgery, and for the efficient production of steam for laser enamel ablation in certain types of laser dentistry. trivalent element, pure erbium metal is malleable (or easily shaped), soft yet stable in air, and does not oxidize as quickly as some other rare-earth metals. Its salts are rose-coloured, and the element has characteristic sharp absorption spectra bands in visible light, ultraviolet, and near infrared. Otherwise it looks much like the other rare earths. Its sesquioxide is called erbia. Erbium's properties are to a degree dictated by the kind and amount of impurities present. Erbium does not play any known biological role, but is thought to be able to stimulate metabolism. Erbium metal tarnishes slowly in air and burns readily to form erbium(III) oxide: 4 Er + 3 O2 → 2 Er2O3 Erbium is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form erbium hydroxide: 2 Er (s) + 6 H2O (l) → 2 Er(OH)3 (aq) + 3 H2 (g) Naturally occurring erbium is composed of 6 stable isotopes, 162 Er, 164 Er, 166 Er, 167 Er, 168 Er, and 170 Er with 166 Er being the most abundant (33.503% natural abundance). 29 radioisotopes have been characterized, with the most stable being 169 Er with a half-life of 9.4 days, 172 Er with a half-life of 49.3 hours, 160 Er with a half-life of 28.58 hours, 165 Er with a half-life of 10.36 hours, and 171 Er with a half-life of 7.516 hours. All of the remaining radioactive isotopes have half-lives that are less than 3.5 hours, and the majority of these have half-lives that are less than 4 minutes. This element also has 13 meta states, with the most stable being 167m. Er with a half-life of 2.269 seconds. Erbium (for Ytterby, a village in Sweden) was discovered by Carl Gustaf Mosander in 1843. Mosander separated "yttria" from the mineral gadolinite into three fractions which he called yttria, erbia, and terbia. He named the new element after the village of Ytterby where large concentrations of yttria and erbium are located. Erbia and terbia, however, were confused at this time. After 1860, terbia was renamed erbia and after 1877 what had been known as erbia was renamed terbia. Fairly pure Er2O3 was independently isolated in 1905 by Georges Urbain and Charles James. Reasonably pure metal wasn't produced until 1934 when Klemm and Bommer reduced the anhydrous chloride with potassium vapor. It was only in the 1990s that the price for Chinese-derived erbium oxide became low enough for erbium to be considered for use as a colorant in art glass. The concentration of erbium in the Earth crust is about 2.8 mg/kg and in the sea water 0.9 ng/L.This concentration is enough to make erbium about 45th in elemental abundance in the Earth's crust. Erbium metal is obtained from its oxide or salts by heating with calcium at 1450 °C under argon atmosphere. Erbium's everyday uses are varied. It is commonly used as a photographic filter and because of its resilience it is useful as a metallurgical additive. Other uses: Used in nuclear technology in neutron- absorbing control rods. When added to vanadium as an alloy, erbium lowers hardness and improves workability. Erbium oxide has a pink color, and is sometimes used as a colorant for glass, cubic zirconia and porcelain. The glass is then often used in sunglasses and cheap jewelry. As with the other lanthanides, erbium compounds are of low to moderate toxicity, although their toxicity has not been investigated in detail. Metallic erbium in dust form presents a fire and explosion hazard. References: ^ Emsley, John (2001). "Erbium". Nature's Building Blocks: An A-Z Guide to the Elements. Oxford, England, UK: Oxford University Press. pp. 136–139. ISBN 0-19- 850340-7. ^ M. Jackson (2000). "Magnetism of Rare Earth". The IRM quarterly 10 (3): 1. ^ Yuta Sato; Kazu Suenaga; Shingo Okubo; Toshiya Okazaki; Sumio Iijima (2007). "Structures of D5d-C80 and Ih-Er3N@C80 Fullerenes and Their Rotation Inside Carbon Nanotubes Demonstrated by Aberration-Corrected Electron Microscopy". Nano Letters 7 (12): 3704. Bibcode 2007NanoL...7.3704S. doi:10.1021/nl0720152. ^ "Chemical reactions of Erbium". Webelements. Retrieved 2009-06-06. ^ Georges, Audi (2003). "The NUBASE Evaluation of Nuclear and Decay Properties". Nuclear Physics A (Atomic Mass Data Center) 729: 3–128. Bibcode 2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. ^ C. G. Mosander (October 1843) "On the new metals, Lanthanium and Didymium, which are associated with Cerium; and on Erbium and Terbium, new metals associated with Yttria," Philosophical Magazine, series 3, vol. 23, no. 152, pages 241-254. Note: The first part of this article, which does NOT concern erbium, is a translation of: C. G. Mosander (1842) "Något om Cer och Lanthan" [Some (news) about cerium and lanthanum], Förhandlingar vid de Skandinaviske naturforskarnes tredje möte (Stockholm) [Transactions of the Third Scandinavian Scientist Conference (Stockholm)], vol. 3, pages 387-398. ^ Aaron John Ihde (1984). The development of modern chemistry. Courier Dover Publications. pp. 378–379. ISBN 0486642356. ^ a b c Patnaik, Pradyot (2003). Handbook of Inorganic Chemical Compounds. McGraw-Hill. pp. 293–295. ISBN 0070494398. Retrieved 2009- 06-06. ^ Early paper on the use of displacement ion-exchange chromatography to separate rare earths: Spedding, F.H.; Powell, J.E. (1954). "A practical separation of yttrium group rare earths from gadolinite by ion-exchange". Chemical Engineering Progress 50: 7–15. ^ edited by Theodore A. Parish, Vyacheslav V. Khromov, Igor Carron. (1999). "Use of UraniumErbium and PlutoniumErbium Fuel in RBMK Reactors". Safety issues associated with Plutonium involvement in the nuclear fuel cycle. CBoston: Kluwer. pp. 121–125. ISBN 9780792355939.