Europium(II) chemistry is very similar to barium(II) chemistry, as they have similar ionic radii.
Europium (chemical symbol Eu, atomic number 63) is the most reactive of the rare earth elements.
Europium is commonly included in trace element studies in geochemistry and petrology to understand the processes that form igneous rocks (rocks that cooled from magma or lava).
Europium is never found in nature as a free element; however, there are many minerals containing europium, with the most important sources being bastnдsite and monazite.
Europium is an inner transition metal (or lanthanide) that lies in period six of the periodic table, between samarium and gadolinium.
Naturally occurring europium is composed of two stable isotopes, 151-Eu and 153-Eu, with 153-Eu being the most abundant (52.2 percent natural abundance).
Europium(II) compounds tend to predominate, in contrast to most lanthanides (which generally form compounds with an oxidation state of +3).
Europium has also been identified in the spectra of the Sun and certain stars.
The toxicity of europium compounds has not been fully investigated, but there are no clear indications that europium is highly toxic compared to other heavy metals.
The Navajo comprise a large Nation in New Mexico, Arizona, and since 1500, the area in Utah near Four Corners.
Europium oxide (Eu2O3) is widely used as a red phosphor in television sets and fluorescent lamps, and as an activator for yttrium-based phosphors.
Europium fluorescence is used to interrogate biomolecular interactions in drug-discovery screens.