Element 61 · Lanthanide (Rare Earth)
Promethium
The only naturally radioactive lanthanide — promethium has no commercial scrap relevance.
Element Facts
SYMBOL
Pm
ATOMIC NO.
61
ATOMIC WEIGHT
145
CATEGORY
Lanthanide (Rare Earth)
PERIOD
Period 6
GROUP
Group 3
Origins
Promethium was the last lanthanide to be discovered and is the only lanthanide with no stable isotopes. First isolated in 1945 by Jacob Marinsky, Lawrence Glendenin, and Charles Coryell at Oak Ridge National Laboratory from uranium fission products. Named after Prometheus, the Titan who stole fire from the gods, symbolising the use of nuclear energy to create new elements. It had previously been predicted and searched for, with several false claims of discovery during the early 20th century.
Key Properties
Promethium is element 61, a silvery radioactive lanthanide with no stable isotopes. It does not occur naturally in the Earth's crust in detectable quantities and is produced only as a by-product of uranium fission in nuclear reactors. Its longest-lived isotope (Pm-145) has a half-life of 17.7 years.
Modern Applications
Some nuclear-powered watch dials and instrument lighting (replaced radium in the 1960s for medical safety reasons). Specialist nuclear research applications.
At the Yard
Why QuickStop Metals doesn’t buy Promethium:
Promethium is radioactive and produced only in nuclear facilities. There is no scrap market — it is handled exclusively by licensed nuclear materials operators.
Market Value
No significant commercial market. Promethium-147 is used in small quantities for luminous paint (replacing radium) and in atomic batteries. Produced as a fission product in nuclear reactors. Not a scrap material.