(Chemical symbol: Yt)A. rare earth. Yttriumis a silvery metallic element that is used in thermal spraying processes, and is of strategic value in high-temperature alloys. It is added to magnesium and aluminum alloys to increase strength. Atomic number, 39; atomic weight 88.92, density 5.51 g/cm3 (0.199 Ib/in3), with a melting point of approximately 1538°C (2800°F).
