pra·se·o·dym·i·um (prā′zē-ō-dĭmē-əm, prā′sē-)
n. Symbol Pr
A soft, silvery, malleable, ductile element of the lanthanide series that develops a characteristic green tarnish in air. It occurs naturally with other rare-earth elements in the minerals monazite and bastnaesite and is used to color glass and ceramics yellow, as a core material for carbon arcs, and in metallic alloys. Atomic number 59; atomic weight 140.908; melting point 931°C; boiling point 3,520°C; specific gravity 6.773; valence 3, 4. See Periodic Table.
[German Praseodym : Greek praseos, variant of prasios, leek-green (from prason, leek) + German -dym, didymium.]
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