Dysprosium chips
21 July 2023
Dysprosium, atomic number 66 and symbol Dy, is rare-earth metal with a silvery color. It is not found in nature as a free element, existing only in compounds with other elements. It has few practical uses, but it is used in the control rods of nuclear reactors and in some data-storage applications.
The name is a modern Latin coinage, formed from the Greek δυσπρόσιτος (dysprósitos, meaning inaccessible). Dysprosium was first identified and named by Paul Émile Lecoq de Boisbaudran in 1886, but it was not successfully isolated until the 1950s. Lecoq de Boisbaudran wrote two notes on his discovery in May 1886. One is titled Sur le Dysprosium (On Dysprosium), and in the other, L’Holmine (ou Terre X de M. Soret) Contient au Moins Deux Radicaux Mètalliques (Holmine [or M. Soret’s “Earth X”] Contains at Least Two Metallic Radicals), he explains the name:
Comme les bandes 640,4 et 536,3 sont surtout celles qui ont servi à M. Soret et à M. Clève pour reconnaître la présence d'un élément nouveau dans l'ancienne erbine, je propose de conserver le nom d'holmium à l'élé- ment producteur de ces bandes et d'appeler dysprosium (symbole Dy)* le métal qui donne les bandes 753 et 451,5.
(As bands 640.4 and 536.3 are above all those which were used by M. Soret and M. Clève to recognize the presence of a new element in the old erbine, I propose to retain the name of holmium for the element producing these bands and to call dysprosium (symbol Dy) the metal which gives the bands 753 and 451.5.)
The footnote gives the Greek root:
* De Δυσπρόσιτος: d’un abord difficile.
(* Of Dysprósitos: inaccessible.)
Sources:
Lecoq de Boisbaudran, Paul Émile. “L’Holmine (ou Terre X de M. Soret) Contient au Moins Deux Radicaux Mètalliques.” Comptes Rendus Hebdomadaires Des Séances de l’Académie des Sciences, 3 May 1886, 1003–1004 at 1004. HathiTrust Digital Archive.
———. “Sur le Dysprosium.” Comptes Rendus Hebdomadaires Des Séances de l’Académie des Sciences, 3 May 1886, 1005–1006. HathiTrust Digital Archive.
Miśkowiec, Pawel. “Name Game: The Naming History of the Chemical Elements: Part 2—Turbulent Nineteenth Century,” Foundations of Chemistry, 8 December 2022.
Oxford English Dictionary, second edition, 1989, s.v. dysprosium, n.
Photo credit: Materialscientist (anonymous photographer), 2009. Wikimedia Commons. Licensed under a Creative Commons Attribution-Share Alike 3.0 Unported license.