|Atomic mass||174.967 amu|
Lutetium was discovered in 1907, is the heaviest of the rare-earths and marks the end of the lanthanide series of elements. The discovery of lutetium was made possible by significant advances in the technology for separating small amounts of compounds that have similar chemical properties. In fact, most of the rare-earth elements were discovered with the aid of ion-separation techniques.
Lutetium is also the hardest of the rare-earths. It has a silvery-white color and is fairly stable under normal atmospheric conditions. Obtained from monazite sand with other lanthanides, lutetium content is on the order of 0.003%.
With many of its chemical and physical properties unknown, lutetium is one of the few natural elements that has no practical application. One of its few uses is as a catalyst.