Editing Neodymium (section)

==History==
[[File:Auer von Welsbach.jpg|upright=0.9|thumb|[[Carl Auer von Welsbach]] (1858–1929), who discovered neodymium in 1885<ref name="Marshall">{{cite journal |last1=Marshall |first1=James L. Marshall |last2=Marshall |first2=Virginia R. Marshall |title=Rediscovery of the elements: The Rare Earths–The Last Member |journal=The Hexagon |date=2016 |pages=4–9 |url=https://chemistry.unt.edu/sites/default/files/users/owj0001/rare%20earths%20III_0.pdf |access-date=30 December 2019}}</ref>]]

In 1751, the Swedish mineralogist [[Axel Fredrik Cronstedt]] discovered a heavy mineral from the mine at [[Bastnäs]], later named [[cerite]]. Thirty years later, fifteen-year-old [[Wilhelm Hisinger]], a member of the family owning the mine, sent a sample to [[Carl Scheele]], who did not find any new elements within. In 1803, after Hisinger had become an ironmaster, he returned to the mineral with [[Jöns Jacob Berzelius]] and isolated a new oxide, which they named ''ceria'' after the [[dwarf planet]] [[Ceres (dwarf planet)|Ceres]], which had been discovered two years earlier.{{sfn|Emsley|2011|page=100}} Ceria was simultaneously and independently isolated in Germany by [[Martin Heinrich Klaproth]].{{sfn|Greenwood|Earnshaw|1997|p=1424}} Between 1839 and 1843, ceria was shown to be a mixture of oxides by the Swedish surgeon and chemist [[Carl Gustaf Mosander]], who lived in the same house as Berzelius; he separated out two other oxides, which he named ''lanthana'' and ''didymia''.<ref name="XI">{{cite journal | doi = 10.1021/ed009p1231 | last = Weeks | first = Mary Elvira |author-link=Mary Elvira Weeks| title = The Discovery of the Elements: XI. Some Elements Isolated with the Aid of Potassium and Sodium:Zirconium, Titanium, Cerium and Thorium | journal = The Journal of Chemical Education | date = 1932 | volume = 9 | issue = 7 | pages = 1231–1243 |bibcode = 1932JChEd...9.1231W }}</ref><ref name="Weeks">{{cite book |last1=Weeks |first1=Mary Elvira |title=The discovery of the elements |date=1956 |publisher=Journal of Chemical Education |location=Easton, PA |url=https://archive.org/details/discoveryoftheel002045mbp |edition=6th }}</ref><ref name="Virginia">{{cite journal |last1=Marshall |first1=James L. Marshall |last2=Marshall |first2=Virginia R. Marshall |title=Rediscovery of the elements: The Rare Earths–The Confusing Years |journal=The Hexagon |date=2015 |pages=72–77 |url=http://www.chem.unt.edu/~jimm/REDISCOVERY%207-09-2018/Hexagon%20Articles/rare%20earths%20II.pdf |access-date=30 December 2019}}</ref> He partially decomposed a sample of [[cerium nitrate]] by roasting it in air and then treating the resulting oxide with dilute [[nitric acid]]. The metals that formed these oxides were thus named ''lanthanum'' and ''[[didymium]]''.<ref>See:
* {{Cite book |author=Académie des sciences (France) |url=http://archive.org/details/ComptesRendusAcademieDesSciences0008 |title=Comptes rendus Academie des sciences 0008 |date=1839  |language=fr}} From p. 356: ''"L'oxide de cérium, extrait de la cérite par la procédé ordinaire, contient à peu près les deux cinquièmes de son poids de l'oxide du nouveau métal qui ne change que peu les propriétés du cérium, et qui s'y tient pour ainsi dire caché. Cette raison a engagé M. Mosander à donner au nouveau métal le nom de ''Lantane''."'' (The oxide of cerium, extracted from cerite by the usual procedure, contains almost two fifths of its weight in the oxide of the new metal, which differs only slightly from the properties of cerium, and which is held in it so to speak "hidden". This reason motivated Mr. Mosander to give to the new metal the name ''Lantane'').
* {{Cite book |url=https://books.google.com/books?id=dF1KiX7MbSMC&pg=PA390 |title=Philosophical Magazine |date=1839 |publisher=Taylor & Francis |language=en}}</ref> Didymium was later proven to not be a single element when it was split into two elements, praseodymium and neodymium, by [[Carl Auer von Welsbach]] in [[Vienna]] in 1885.<ref>{{cite journal |last1=v. Welsbach |first1=Carl Auer |title=Die Zerlegung des Didyms in seine Elemente |journal=Monatshefte für Chemie und verwandte Teile anderer Wissenschaften |volume=6|issue=1 |year=1885|pages=477–491 |doi=10.1007/BF01554643|s2cid=95838770 }}</ref><ref>{{Cite book|title = Extractive Metallurgy of Rare Earths|last1 = Krishnamurthy|first1 = N.|publisher = CRC Press|year = 2004|isbn = 978-0-203-41302-9|pages = 6|last2 = Gupta|first2 = C. K.}}</ref><!-- The year of discovery is wrong in this book. Confirmed by an email from the author--> Von Welsbach confirmed the separation by [[spectroscopic]] analysis, but the products were of relatively low purity. Pure neodymium was first isolated in 1925. The name neodymium is derived from the Greek words ''neos'' (νέος), new, and ''didymos'' (διδύμος), twin.<ref name="CRC" /><ref name="history">{{cite book|url=https://archive.org/details/naturesbuildingb0000emsl|url-access=registration| pages= [https://archive.org/details/naturesbuildingb0000emsl/page/268 268]–270|title = Nature's building blocks: an A–Z guide to the elements| author =Emsley, John | publisher= Oxford University Press| date = 2003| isbn = 0-19-850340-7}}</ref><ref name="XVI">{{cite journal|last1=Weeks|first1=Mary Elvira|title=The discovery of the elements. XVI. The rare earth elements|journal=Journal of Chemical Education|volume=9|issue=10|year=1932|pages=1751|doi=10.1021/ed009p1751|bibcode=1932JChEd...9.1751W}}</ref>

Double nitrate crystallization was the means of commercial neodymium purification until the 1950s. Lindsay Chemical Division was the first to commercialize large-scale ion-exchange purification of neodymium. Starting in the 1950s, high purity (>99%) neodymium was primarily obtained through an [[ion exchange]] process from [[monazite]], a mineral rich in rare-earth elements.<ref name="CRC" /> The metal is obtained through [[electrolysis]] of its [[halide]] [[Salt (chemistry)|salts]]. Currently, most neodymium is extracted from [[bastnäsite]] and purified by solvent extraction. Ion-exchange purification is used for the highest purities (typically >99.99%). Since then, the glass technology has improved due to the improved purity of commercially available neodymium oxide and the advancement of glass technology in general. Early methods of separating the lanthanides depended on fractional crystallization, which did not allow for the isolation of high-purity neodymium until the aforementioned ion exchange methods were developed after World War II.<ref>{{Citation |last=Cotton |first=Simon A. |title=The Rare Earths, a Challenge to Mendeleev, No Less Today |date=2021 |url=https://doi.org/10.1007/978-3-030-67910-1_11 |work=150 Years of the Periodic Table: A Commemorative Symposium |pages=259–301 |editor-last=Giunta |editor-first=Carmen J. |access-date=2023-06-07 |series=Perspectives on the History of Chemistry |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-67910-1_11 |isbn=978-3-030-67910-1 |s2cid=238942033 |editor2-last=Mainz |editor2-first=Vera V. |editor3-last=Girolami |editor3-first=Gregory S.}}</ref>