Holmium
Name: Holmium
Symbol: Ho
Atomic Number: 67
Mass fraction of the earth’s shell: 1 x 10−4
Melting Point: 1474 °C
Boiling Point: 2695 °C
Electrical Conductivity: 1,24· 106 A·V−1·m−1
Name: Holmium
Symbol: Ho
Atomic Number: 67
Mass fraction of the earth’s shell: 1 x 10−4
Melting Point: 1474 °C
Boiling Point: 2695 °C
Electrical Conductivity: 1,24· 106 A·V−1·m−1
HISTORY
In 1878, a year before Edison invented the light bulb, the Swiss chemists Marc Delafontaine and Jacques-Louis Soret noticed the deviating absorption lines of a new element. They initially named it Element X. One year later, the Swedish chemist Per Theodor Cleve isolated the same element as a yellow oxide from impure erbium. To do this, Cleve separated all the known impurities, and then isolated the rest.
Thirty-two years later, the Swedish chemist Holmberg succeeded in obtaining pure holmium oxide. The name of the element comes from Holmia, the Latin name for Stockholm.
CHARACTERISTICS & EXTRACTION
Holmium is also used in the production of catalysts and glass polishes.
Pole shoes made of holmium generate the strongest magnetic fields and are found in high-performance magnets. Thin-film alloys of holmium-iron, holmium-nickel, and holmium-cobalt are needed to produce magnetic bubble storage. Other applications include control rods in breeder reactors and microwave components in medical technology. In photometers, holmium oxide imparts a yellow colour to the glass.
