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For fluorescent lamps.
|Atomic Number:||65||Atomic Symbol:||Tb|
|Atomic Weight:||158.9254||Electron Configuration:||2-8-26-9-2|
|Melting Point:||1360oC||Boiling Point:||3041oC|
|Description:||Silvery rare earth metal.|
History(Ytterby, a villiage in Sweden) Discovered by Mosander in 1843.
Terbium is a member of the lanthanide or "rare earth" group of elements.
- It is found in cerite, gadolinite, and other minerals along with other rare
- It is recovered commercially from monazite in which it is present to the
extent of 0.03%, from xenotime, and from euxenite, a complex oxide containing 1%
or more of terbia.
- Terbium has been isolated only in recent years with the development of
ion-exchange techniques for separating the rare-earth elements.
- As with other rare earths, it can be produced by reducing the anhydrous
chloride or fluoride with calcium metal in a tantalum crucible.
- Calcium and tantalum impurities can be removed by vacuum remelting.
- Other methods of isolation are possible.
- Terbium is reasonably stable in air.
- It is a silver-gray metal, and is malleable, ductile, and soft enough to be
cut with a knife.
- Two crystal modifications exist, with a transformation temperature of 1289C.
- Twenty one isotopes with atomic masses ranging from 145 to 165 are
- The oxide is a chocolate or dark maroon color.
- Sodium terbium borate is used in solid-state devices.
- The oxide has potential application as an activator for green phosphors used
in color TV tubes.
- It can be used with ZrO2 as a crystal stabilizer of fuel cells which operate
at elevated temperature.
- Few other uses have been found.
CostsThe element is priced at about $30/g (99.9%).