Holmium
A rare-earth element with the highest magnetic moment.
Holmium is a chemical element with the symbol Ho and atomic number 67. It is a rare-earth element and the eleventh member of the lanthanide series. It is notable for having the highest magnetic permeability and magnetic saturation of any element, making it essential for the pole pieces of the strongest static magnets, and it is also used as a burnable poison in nuclear reactors due to its strong neutron absorption.
- symbol
- Ho
- atomic_number
- 67
- discovered_by
- Jacques-Louis Soret, Marc Delafontaine, and Per Theodor Cleve
- element_category
- Lanthanide
- key_property
- Highest magnetic permeability and magnetic saturation of any element
Lore & Background
Using methods developed by Carl Gustaf Mosander, Cleve removed known contaminants from erbia and obtained two new materials: a brown substance he named holmia (after Holmia, the Latin name for Stockholm) and a green one he named thulia. Holmia was later identified as holmium oxide, and thulia as thulium oxide.
Reader's Guide
Holmium's significance lies in its unique magnetic and nuclear properties. It has the highest magnetic moment (10.6 μB) of any naturally occurring element and is ferromagnetic below 19 K, making it crucial for the pole pieces of the strongest static magnets. Its strong neutron absorption also makes it valuable as a burnable poison in nuclear reactors. In nature, holmium occurs with other rare-earth metals, primarily in minerals monazite and gadolinite, and is commercially extracted from monazite using ion-exchange techniques. Its compounds are typically trivalent, and trivalent holmium ions have fluorescent properties used in lasers and glass colorants. Holmium is relatively rare, making up 1.4 parts per million of the Earth's crust, similar to tungsten. The element's name derives from Holmia, the Latin name for Stockholm.
Did You Know?
- Holmium has the highest magnetic permeability and magnetic saturation of any element.
- The element's name comes from Holmia, the Latin name for Stockholm.
Frequently Asked Questions
Who is Holmium?
Holmium is a soft, silvery, malleable rare-earth metal with the symbol Ho and atomic number 67. It is the eleventh member of the lanthanide series and is notably resistant to corrosion.
What makes Holmium stand out among all elements?
Holmium possesses the highest magnetic permeability and magnetic saturation of any element on the periodic table. This record-breaking magnetic moment is what distinguishes it from every other known substance.
What is Holmium actually used for?
Its unmatched magnetic strength makes Holmium indispensable for the pole pieces of the strongest static magnets in existence. Without it, those ultra-powerful permanent magnets simply could not be manufactured.
Where does Holmium sit in the periodic table?
Holmium occupies position 67 in the lanthanide row, specifically as the eleventh element of that series. It is classified as a rare-earth element, sharing that broader family with its neighboring f-block metals.
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