The existence of promethium was predicted in 1902, but proof of its existence was only obtained during analysis of by-products of uranium fission produced in a nuclear reactor in 1944. Promethium is named after the Greek mythological figure Prometheus.
Promethium does not occur in any known mineral deposits in abundance.
Applications of Promethium:
- Energy: Promethium could be used to make a nuclear powered battery, which in operation would use the beta particles emitted by the decay of promethium to give off light. This light would then be converted into electricity by a device similar to a solar cell. It is expected that this type of battery could provide power for as long as five years.
- Instrumentation: Promethium can also be used as a portable x-ray source, and as a source of radioactivity for gauges that measure thickness. It may also be useful in lasers that can be used to communicate with submerged submarines.
- Illumination Sources: Promethium chloride, mixed with zinc sulfide, was previously used as a luminous paint for watches, compass and instrument dials after the use of radium was discontinued.