At A Glance: Ho
|Atomic Radius:||216 pm (Van der Waals)|
|Melting Point:||1474 °C|
|Boiling Point:||2700 °C|
|Sources: Holmium is found in the minerals monazite and gadolinite, and is usually commercially extracted from monazite using ion exchange techniques.
Uses: Holmium is one of the least abundant Rare Earth elements and has few commercial uses.
Content provided by Los Alamos National Laboratory. Used with permission.
From the Latin word Holmia meaning Stockholm. The special absorption bands of holmium were noticed in 1878 by the Swiss chemists Delafontaine and Soret, who announced the existence of an “Element X.” Cleve, of Sweden, later independently discovered the element while working on erbia earth. The element is named after Cleve’s native city. Holmia, the yellow oxide, was prepared by Homberg in 1911. Holmium occurs in gadolinite, monazite, and in other rare-earth minerals. It is commercially obtained from monazite, occurring in that mineral to the extent of about 0.05%. It has been isolated by the reduction of its anhydrous chloride or fluoride with calcium metal.
Pure holmium has a metallic to bright silver luster. It is relatively soft and malleable and is stable in dry air at room temperature but rapidly oxidizes in moist air and at elevated temperatures. The metal has unusual magnetic properties. Few uses have yet been found for the element. The element, as with other rare earths, seems to have a low acute toxic rating.
Source: Los Alamos National Laboratory