Holmium
| Holmium
| |
|---|---|
| Symbol | Ho |
| Atomic number | 67 |
| Atomic mass | 164.9303 amu |
Holmium was discovered in 1879.
Distinguishing properties
Holmium has a bright, silvery luster. It is fairly soft, much like lead and can be pounded or rolled in thin sheets. It is fairly stable in normal room environment, but it tends to corrode with a dull yellowish oxide film under conditions of high temperature and humidity.
Occurrence
Holmium belongs to the lanthanide series of rare earths. Most commercial-grade holmium is obtained from monazite sand, which is a mixture of phosphates of calcium, thorium, cerium, and most of the other rare earths. This sand is often 50% rare earth by mass, with approximately 0.05% being holmium.
Usage
Like dysprosium, holmium is a metal which can absorb fission-bred neutrons. It is used in nuclear reactors to keep atomic chain reaction from running out of control.
