Lutetium

Element Name: Lutetium
Atomic Number: 71
Atomic Mass: 174.9668
Atomic Symbol: Lu
Melting Point: 1663° C
Boiling Point: 3402° C

Lutetium is the final lanthanide, and the last naturally occurring one to be found in nature. It is silvery-white, and will slowly tarnish in air. It’ll burn to form the oxide if heated about 150°C. It is the hardest and densest of all the lanthanides, which may sound more impressive than it actually is considering common cutlery can cleanly cut half of the others. It is typically trivalent and tends to form colorless compounds. There are two naturally occurring isotopes of Lutetium. The vast majority is the stable 175Lu while a small minority is the radioactive 176Lu. 35 Isotopes of Lutetium have been found. It is named for Lutetia, the Latin word for Paris where the alternative German cassiopeium is derived from the constellation.

Interesting Facts:

Georges Urbain and Carl Auer von Welsbach contested each other in the discovery of lutetium. Ultimately Urbain won, but Welsbach’s chosen name (cassiopeium/cassiopium) survived in Germany until the 1950s. Lutetium-176 is used in lutetium-hafnium dating to determine the age of meteorites.

Sources:

Lutetium is not found in its elemental form in nature, rather it’s found in minerals. Only monazite offers it in any real value – at 0.0001% by weight. In the crust lutetium makes up 0.5 parts per million, and unsurprisingly very little lutetium is made in a year. Only about 10 tons are made a year. China, the U.S., Brazil, India, Sri Lanka, and Australia are the main mining areas. Pure lutetium is very rare and expensive at the price of $10,000 per kilogram, making it about a quarter as expensive as gold.

Industrial Uses:

Lutetium is rare and expensive, thus it has few commercial uses. It can be used as a catalyst in petroleum cracking and can be used in alkylation, hydrogenation, and polymerization. Like many other rare earth elements, it can be used as a dopant in several compounds that other rare earths are the star. It does have a naturally occurring radioactive isotope, which is where most of its practical applications come from. In nuclear medicine Lutetium oxyorthosilicate is the preferred compound in PET scans. An artificial isotope of lutetium (177Lu) is used to treat tumors. Lutetium tantalite is the densest stable white material which makes it a good choice for x-ray phosphors.

References:

“Facts About Lutetium.” Livescience. Livescience.com, 24 July 2013. Web. 26 July
2016.
“Lutetium.” Wikipedia. Wikimedia Foundation, n.d. Web. 26 July 2016.
“Lutetium Element Facts / Chemistry.” Chemicool. Chemicool.com, 17 Oct. 2012.
Web. 26 July 2016.
Gray, Theodore W., and Nick Mann. The Elements: A Visual Exploration of Every
Known Atom in the Universe. New York: Black Dog & Leventhal, 2009. Print.