Promezio (PM) Promethium

An Artificial Element

Promethium is the only rare earth element that does not occur naturally on Earth in significant quantities. With a half-life of only 17.7 years for its most stable isotope (Pm-145), any primordial promethium disappeared billions of years ago.

Laboratory Production

Today promethium is produced artificially in nuclear reactors by fission of uranium or by bombarding neodymium with neutrons. Its global production is extremely limited, estimated at a few tens of grams per year.

Specialized Applications

Despite its rarity, promethium finds use in miniaturized nuclear batteries for space and military applications. Its decay produces a reliable and long-lasting energy source for devices that must operate under extreme conditions.