Discovery of promethium

Promethium was identified in 1945 by the American chemists Jacob Marinsky, Lawrence Glendenin and Charles Coryell at the Clinton Laboratories in Oak Ridge, Tennessee, who separated it from the products of uranium fission. For decades chemists had suspected that element 61 should exist, and several claims of its discovery in nature had proved false. The announcement was delayed until 1947 because of wartime secrecy. It was named after Prometheus, the figure in Greek mythology who stole fire from the gods, to symbolise both the daring and the danger of harnessing nuclear energy. Promethium has no stable isotopes, and it is vanishingly rare in nature. It has been used in luminous paint, in nuclear batteries for spacecraft and in thickness gauges.

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