Europium is a silvery-white metal that will ignite in air at about 150 °C to 180 °C. The metal is soft, very ductile, and the most reactive of the rare-earth metals. The element has two valence states, +2 and +3, and is divalent in the metallic state. Europium metal has a body centered cubic structure, a density of 5.259 gm/cm3, a melting point of 826 °C, and a boiling point of 1439 °C. Europium oxide, or europia, occurs as a sesquioxide with the formula Eu2O3, however it will readily form divalent compounds. The trivalent oxide is a light-pink powder with a specific gravity of 7.30 gm/cm3, a melting point of 2350 °C and a formula weight of 351.92. The oxide is hygroscopic and will readily absorb moisture and carbon dioxide from the atmosphere.

• Taggant phosphors with europium are used as anti-forgery marks on Euro and various currencies.
• The primary use of europium is in phosphors used in pilot display screens, televisions (reddish-orange), and trichromatic fluorescent lights (reddish-orange and blue).
• Europium EuB6 absorbs neutrons in fast breeder nuclear reactors to control the fission process.