Europium is the sixty third element on the periodic table, giving it sixty three protons and electrons. Like the other rare earth elements, europium cannot be found free in nature and instead can be found in a variety of minerals including bastnäsite, monazite, xenotime and loparite.
The element is typically characterized as a transition metal, or sometimes as an inner transition metal. Given the sheer number of transition metals it is difficult to define any definite characteristics but, generally, transition metals are paramagnetic with more than one oxidation states. Also, metals typically (though not always) have high electrical conductivity as well as high density and high melting and boiling points.
Within the transition metals, europium is classified as a lanthanide. All lanthanides are considered rare earth elements on the periodic table. Despite the name however, rare earth elements are not necessarily rare – they’re just notoriously hard to find in large enough quantities to be useful. Often found together, rare earth elements are difficult to separate.
A moderately hard, ductile, silvery metal, europium has the second lowest melting point and the lowest density of all lanthanides. Naturally occurring europium has only two isotopes, one of which is stable.
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