Holmium

Holmium was discovered in 1878 by the Swiss chemists Marc Delafontaine and Jacques-Louis Soret, who saw its spectral signature, and independently by the Swede Per Teodor Cleve, who isolated it and named it. The name comes from Holmia, the Latin name for Stockholm, Cleve's home city. Holmium is a soft, silvery rare-earth metal notable for having the highest magnetic strength of any element, and it is used in the cores of powerful magnets and in certain surgical lasers. Having the greatest magnetic strength of any element, holmium is used to concentrate the fields of the strongest laboratory magnets, in solid-state lasers for medicine and industry, and as a yellow colourant in glass and cubic zirconia.

The holmium:YAG laser has become a mainstay of modern urology, precisely vaporising kidney and ureteral stones during minimally invasive procedures with a safety record that has made it a standard tool in hospitals worldwide, a distinctly practical modern legacy for an element first noticed only as a faint line in a mineral spectrum. Because of its powerful magnetic moment, holmium is also alloyed into the innermost pole pieces of the strongest steady-state laboratory magnets, briefly boosting the peak field beyond what other materials alone can sustain.

Holmium's name is a scholarly Latinism honouring Stockholm, the Swedish capital near which the Ytterby quarry lies and where much of the rare-earth work was done. It joins the geographical namings that cluster around the discovery of the lanthanides, most of them Scandinavian, reflecting the Swedish and Nordic chemists who dominated the field. Cleve, who named holmium, drew two elements from the same work, naming the other thulium after Thule, the classical name for the far north. Holmium has no mythological or alchemical past, being a product of nineteenth-century spectroscopy and fractional separation; its name simply plants the flag of Stockholm in the periodic table, a companion to the nearby village of Ytterby that named so many of its neighbours.

Priority for holmium is genuinely shared rather than settled on one name: Delafontaine and Soret observed its distinctive spectral absorption bands first, while Cleve, working independently and apparently unaware of their spectroscopic work, isolated the actual substance and supplied the name that was ultimately adopted, so modern references typically credit the discovery to all three. Cleve's naming choice for holmium came in the same short burst of productivity that also gave the periodic table thulium, a remarkable pace even by the standards of the crowded rare-earth decade of the 1870s.