Lutetium

Lutetium is a silvery-white lanthanide metal. Like other rare-earth elements, it is found mixed with related elements rather than in deposits of its own, making it difficult to separate. It occurs in minerals such as monazite, where it is present only in tiny amounts; commercial lutetium is recovered as a by-product when rare-earth minerals are processed. Further separation uses ion-exchange methods, and the metal can be made by reducing a lutetium compound. Lutetium has a few specialized uses. Stable lutetium can help catalysts refine petroleum, while compounds containing lutetium are used in scintillators that convert X-rays into visible light, including detectors for medical PET scans. A different form, the radioactive isotope lutetium-177, is used in targeted treatments for some cancers; this medical use belongs to that isotope, not to ordinary lutetium metal.