What element has the symbol 'Eu'?

The story behind the answer

Eu is the chemical symbol for Europium, a silvery lanthanide (atomic number 63) named after the continent Europe. The other options aren’t real element names. Europium was identified in the 1890s by French chemist Eugène-Anatole Demarçay.

Europium is famous for its bright red phosphorescence: europium-doped compounds make the red pixels in TV and LED displays and help secure euro banknotes under UV light. It also strongly absorbs neutrons, giving it niche nuclear uses. Memory tip: Eu = EU, the European Union → Europium, the element named for Europe.