Eu153

Eu-153 is a stable isotope of the element europium (Eu) with mass number 153. It is one of the two naturally occurring isotopes of europium, the other being Eu-151. In nature, europium occurs mainly as Eu-151 (~47.8%) and Eu-153 (~52.2%), and both isotopes are stable and do not decay under ordinary conditions. For Eu-153, the nucleus contains 63 protons and 90 neutrons.

Occurrence and production: Eu-153 is found in rare-earth minerals such as bastnäsite, monazite, and xenotime, where europium occurs together with other lanthanides. Commercial production involves mining these minerals and separating europium chemically, with the natural isotopic ratio typically preserved unless isotope separation is pursued for specialized applications.

Properties and applications: The stable isotopic composition of europium, including Eu-153, is used as a reference in isotope-ratio measurements and for calibrating mass spectrometers. Europium-doped phosphors, which rely on Eu ions in suitable oxidation states (such as Eu2+ or Eu3+), are common in lighting and display technologies; while the isotopic mixture has limited direct impact on these phosphor properties, accurate knowledge of isotopic abundances supports geochemical and materials research. In scientific studies, Eu-153 can serve as a non-radioactive tracer in geochemical and metallurgical analyses.

See also: Europium; Isotopes of europium.