What element has the symbol 'Pr'?

The story behind the answer

Pr is the chemical symbol for praseodymium, a soft, silvery lanthanide (rare-earth) element. Its symbol mirrors the element’s name: Pra-seodymium → Pr. By contrast, Promethium is Pm, Protactinium is Pa, and Palladium is Pd.

Praseodymium was isolated in 1885 by Carl Auer von Welsbach when he split “didymium” into neodymium and