I have compiled a list of sources for the elements that are available to the amateur chemist. Europium will be discussed here.
Europium is one of the more expensive rare earth metals, because of its high reactivity. For some reason, europium has a reactivity similar to calcium, corroding in moist air and reacting vigorously with water, producing the yellowish hydroxide. Europium is also the lightest rare earth metal. Most europium compounds are whitish but some are yellow; the sulfuric acid solution of europium(III) is reported to be pink.
In element form: No sources found.
In compound form: Europium-doped yttrium oxide is used to make phosphors in CFL bulbs. Red phosphors contain europium(III), while blue ones contain europium(II). Yttrium vanadata, used as a phosphor in mercury vapor bulbs, also contains a europium dopant.
Here is my sample of europium. It is a fluorescent bulb contain europium-doped phosphors.