Lutetium is a metallic chemical element classified among the lanthanides on the periodic table of elements. This element is fairly rare and difficult to extract in a pure form, and as a result it does not have a wide number of commercial uses. Pure lutetium tends to be quite costly, due to the difficulties involved in the separation process; prices fluctuate, but it tends to be more expensive than comparable metals. The primary source for the world's lutetium is the mineral monzanite, and impurities in other lanthanide metals like yttrium.
When lutetium is isolated, the metal proves to be silvery white in color. It is the heaviest and hardest of the lanthanide metals. The element is identified with the symbol Lu on the periodic table of elements, and it has an atomic number of 71. The element is also extremely corrosion resistant, and it has a high melting point in comparison to other lanthanide metals.
Credit for the discovery of this element goes to Georges Urbain of France, although the element was also simultaneously discovered by Carl Auer von Welsbach, who proposed the name “cassiopium,” and Charles James. Urbain was given the privilege of naming the element, initially calling it lutecium, after the Latin name for Paris, France. Ultimately, the name of the element was changed to lutetium. Some people in Germany refer to the element as cassiopium, although this use is frowned upon by the International Union of Pure and Applied Chemistry (IUPAC), which oversees issues of elemental nomenclature, among other things.
Because lutetium is so difficult to isolate, not very many uses have been developed for it. Lutetium is used in some nuclear applications, and in experimental nuclear medicine. It is also used as a catalyst for cracking hydrocarbon chains in petroleum refineries. Various isotopes of the element are sometimes utilized in dating meteors, and a number of compounds which contain lutetium also have commercial uses.
Like other members of the so-called “rare earth” group, lutetium is mildly toxic. Dust from lutetium can be explosive, and fumes and particles from the element can irritate mucus membranes. People should avoid ingesting the element, and proper face protection should be worn when working with it to prevent harmful levels of exposure. While the element does not appear to be biologically necessary, some studies have shown that lutetium can stimulate metabolic rates.