 Discovery Information
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| Who: C.F. Aver von Welsbach |
| When: 1925 |
| Where: Austria |
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| Name Origin
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| Greek: neos (new) didymos (twin). |
| "Neodymium" in different languages. |
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| Sources
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| Neodymium is never found in nature as the free element. It occurs in ores such as monazite sand and bastnasite. |
| Primary producers are the USA, Brazil, India, Sri Lanka and Australia. Around 7300 tons are produced annually.
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| Abundance
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| Universe: 0.01 ppm (by weight) |
| Sun: 0.003 ppm (by weight) |
| Carbonaceous meteorite: 0.51 ppm |
| Earth's Crust: 33 ppm |
| Seawater: |
| Atlantic surface: 1.8 x 10-6 ppm
|
| Atlantic deep: 3.2 x 10-6 ppm
|
| Pacific surface: 1.8 x 10-6 ppm
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| Pacific deep: 4.8 x 10-6 ppm
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| Uses
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| Used in ceramics to colour glazes, and for special lens with praseodymium. Also to produce bright purple glass and special glass that filters infrared radiation. Neodymium is used in very powerful
permanent magnets - Nd2Fe14B. These magnets are cheaper and also stronger than samarium-cobalt magnets. Neodymium magnets appear in products such as in-ear headphones and computer hard drives.
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| History
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| Neodymium was discovered by Baron Carl Auer von Welsbach, an Austrian chemist, in Vienna in 1885. He separated neodymium, as well as the element praseodymium, from a material known as didymium by means of fractional crystallization of the double ammonium nitrate tetrahydrates from
nitric acid, while following the separation by spectroscopic analysis; however, it was not isolated in relatively pure form
until 1925. The name neodymium is derived from the Greek words neos, new, and didymos, twin. Neodymium is frequently misspelled
as neodynium.
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| Double nitrate crystallization was the means of commercial neodymium purification until the 1950's. The Lindsay Chemical Division
of American Potash and Chemical Corporation, at one time the largest producer of rare earths in the world, offered neodymium
oxide purified in this manner in grades of 65%, 85% and 95% purity, at prices ranging from approximately 2 to 20 dollars per
pound (in 1960 dollars). Lindsay was the first to commercialize large-scale ion-exchange purification of neodymium, using
the technology developed by Frank Spedding at Iowa State University/Ames Laboratory; one pound of their 99% oxide was priced
at $35 in 1960; their 99.9% grade only cost 5 dollars more. Starting in the 1950's, high purity (e.g. 99+%) neodymium was
primarily obtained through an ion exchange process from monazite sand ((Ce,La,Th,Nd,Y)PO4), a material rich in rare earth elements. The metal itself is obtained through electrolysis of its halide salts. Currently,
most neodymium is extracted from bastnaesite, (Ce,La,Nd,Pr)CO3F, and purified by solvent extraction. Ion-exchange purification is reserved for preparing the highest purities (typically
greater than 4N). (When Molycorp first introduced their 98% grade of neodymium oxide in 1965, made by solvent extraction from
Mountain Pass California bastnaesite, it was priced at 5 dollars per pound, for small quantities. Lindsay soon discontinued
operations.) The evolving technology, and improved purity of commercially available neodymium oxide was reflected in the appearance
of neodymium glass made therefrom, that resides in collections today. Early Moser pieces, and other neodymium glass made in
the 1930's, have a more reddish or orange tinge than modern versions, which are more cleanly purple, due to the difficulties
in removing the last traces of praseodymium, when the fractional crystallization technology had to be relied on.
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| Notes
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| Size and strength of volcanic eruption can be predicted by scanning for neodymium isotopes. Small and large volcanic eruptions produce lava with different neodymium isotope composition. From the composition of isotopes, scientists predict how big the coming eruption will be, and use this information to warn residents of the intensity of the
eruption.
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| Hazards
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| Neodymium metal dust is a combustion and explosion hazard. Neodymium dust and salts are very irritating to the eyes and mucous
membranes, and moderately irritating to skin. Breathing the dust can cause lung embolisms, and accumulated exposure damages
the liver. Neodymium also acts as an anticoagulant, especially when given intravenously. Neodymium compounds, like all rare earth metals, are of low to moderate toxicity; however its toxicity has not been thoroughly investigated.
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