Terbium
From Chemistry Resource
| Terbium | |
|---|---|
| Symbol | Tb |
| Atomic number | 65 |
| Atomic mass | 158.9254 amu |
Terbium, discovered in 1843, is a soft, ductile, malleable and silvery element of the lanthanide series.
Distinguishing properties
Terbium is extremely reactive when exposed to air or oxygen and must be kept in an inert atmosphere.
Occurrence
Terbium is a rare-earth metal occurring in low concentration in monazite sand, which is a mixture of phosphate of calcium, thorium, cerium, and most of the other rare-earths. This sand is often 50% rare-earth by mass and about 0.03% terbium. Other sources of terbium are oxide mixtures found in xenotime and euxenite. Such oxide mixtures often contain up to 1% terbium.
Usage
Terbium is used in special lasers and as a dopant in solid-state devices.
