Einsteinium is a completely artifical element (atomic number 99) with a very short half-life (a about 1 and a third years). It was first discovered in the fallout from the detonation of the world’s first hydrogen bomb, code Ivy Mike, detonated at Enewetak Atoll on November 1, 1952.
As a trans-uranic element, it is extremely radioactive. It has no known applications other using it to develop other extremely radioactive trans-uranic elements with even higher atomic numbers – so far, it has been employed successfully in the creation of mendelevium (atomic number 101) and unsuccessfully in the attempted creation of ununennium (atomic number 119).
The Fez — The Dead Milkmen