structural:scholar_edition, structural:reformatting
Stable isotopes

Stable lutetium can be used as catalysts in petroleum cracking in refineries and can also be used in alkylation, hydrogenation, and polymerization applications.

Lutetium aluminium garnet (Al Lu O) has been proposed for use as a lens material in high refractive index immersion lithography. Additionally, a tiny amount of lutetium is added as a dopant to gadolinium gallium garnet, which is used in magnetic bubble memory devices. Cerium-doped lutetium oxyorthosilicate is currently the preferred compound for detectors in positron emission tomography (PET). Lutetium aluminium garnet (LuAG) is used as a phosphor in light-emitting diode light bulbs.

Lutetium tantalate (LuTaO) is the densest known stable white material (density 9.81 g/cm) and therefore is an ideal host for X-ray phosphors. The only denser white material is thorium dioxide, with density of 10 g/cm, but the thorium it contains is radioactive.

Lutetium is also a compound of several scintillating materials, which convert X-rays to visible light. It is part of LYSO, LuAg and lutetium iodide scintillators.

Research indicates that lutetium-ion atomic clocks could provide greater accuracy than any existing atomic clock.