Terbium: 10 Things You Should Know About This Chemical Element

Terbium is yet another of Earth’s Rare Elements . You might recognize it from chemistry class if you paid close attention to the periodic table. It is represented by the periodic symbol Tb and the atomic number of 65. Of course, if you did not pay attention in class, you have a lot to learn about this useful element. Below, we’ve compiled an interesting fact sheet containing 10 things that you should know about this element.

1. Carl Gustaf Mosander, who was a Swedish chemist, discovered terbium. He initially thought it was simply an impurity found in yttrium oxide, but later realized that it was not. Mosander was able to fraction yttria into three separate elements, terbia being the pink-colored fraction (although the color was actually due to erbium).

2. When in its purest form, terbium is a whitish-silver metal that is extremely malleable and ductile. In fact, this metal is so soft that you can actually cut through it by hand with a knife. It is fairly stable when exposed to air.

3. Like many of the lanthanides, terbium is found more commercially rich in China’s ion-adsorption clays. These concentrates possess nearly 1% terbia. Of course, terbium can also be found in monazite and bastnasite. Bastnasite is actually responsible for the largest portion of terbium worldwide.

4. Terbium is routinely separated from rare earths by the process of ion exchange. This process effectively washes out the rare-earths and then production of the metal occurs when fluoride or anhydrous chloride is reduced with the calcium metal.

5. Like most lanthanides, terbium is not found as a free element in nature. However, it can be located with several minerals, including euxenite, monazite and xenotime.

6. Terbium(III) cation appears as a bright, pale yellow due to its brilliant fluorescence. This fluorescence results from the emission line, which is strong and green, that combines with lines that are red and orange.

7. At temperatures 219 K and under, terbium is ferromagnetic. However, at temperatures above 219 K, terbium becomes antiferromagnetic. At 230K, terbium becomes very disordered and is considered paramagnetic.

8. Terbium combines with several elements, including arsenic, boron, carbon, nitrogen, phosphorus, selenium and silicon to form a variety of binary compounds.

9. Terbium is frequently used in applications as a dopant for calcium tungstate, strontium molybdate and calcium fluoride for use in fuel cells and other solid-state devices. It is also used widely in alloys, electronic devices, actuators, sonar systems, magnetomechanical devices, sensors, fluorescent lamps, television tubes and in a variety of biochemistry applications.

10. Terbium does have some minor precautions associated with its use. It is not advised to breath in terbium dust or to consume terbium in any way. Like most of the lanthanides, terbium and its compounds are believed to be of low toxicity with some considering them to be moderately toxic.