Holmium

Holmium(III) oxide

Gadolinitas

HoOxideSolution

Holmium is a chemical element with the symbol Ho and atomic number 67. It is part of the lanthanides series in the periodic table, which is comprised of the 15 metals that, along with scandium and yttrium, are often referred to as the rare earth elements. Holmium was discovered by Swiss chemist Marc Delafontaine and Swedish chemist Per Teodor Cleve in 1878. The element was named after Stockholm, Sweden (in Latin, "Holmia"), where Cleve worked.

Properties

Holmium has some of the most remarkable magnetic properties of any element. It possesses the highest magnetic strength of any element, making it of particular interest for use in strong magnetic fields. Holmium has a bright, silvery-white appearance and is relatively soft and malleable. It is stable in dry air at room temperature but oxidizes rapidly in moist air and at elevated temperatures.

Occurrence

Holmium is not found free in nature but is found in small amounts in minerals such as monazite and bastnäsite, which are rich in rare earth elements. The extraction and purification of holmium from these minerals require complex separation processes, typically involving solvent extraction techniques.

Uses

Due to its unique magnetic properties, holmium has several specialized applications. It is used in the manufacture of extremely strong magnetic fields required in nuclear magnetic resonance spectrometers and in the cores of high-intensity magnets. Holmium-doped yttrium aluminium garnet (Ho:YAG) lasers are used in medical, dental, and fiber-optical applications. These lasers are particularly useful in surgeries, as they can cut through or vaporize tissue with minimal heat damage to surrounding areas.

Safety

As with other rare earth elements, holmium compounds should be handled with care. While metallic holmium does not play a biological role and is not considered highly toxic, its compounds can be hazardous if ingested or if their dust is inhaled. Safety measures should include protective clothing, gloves, and eye protection when handling holmium compounds in the laboratory.

See Also

• Lanthanides
• Rare earth element
• Magnetic materials