cobalt59

Cobalt-59 (59Co) is the only stable isotope of the element cobalt (Co). Its mass number is 59, corresponding to 27 protons and 32 neutrons. In natural cobalt, 59Co accounts for essentially 100 percent of the element's isotopic composition.

Nuclear properties of 59Co include a nonzero nuclear spin of 7/2− and a nonzero magnetic moment, which makes it amenable to nuclear magnetic resonance (NMR) studies. As a stable nucleus, 59Co does not undergo radioactive decay and has no measurable half-life.

Occurrence and production are tied to cobalt’s presence in the Earth’s crust and in stellar nucleosynthesis. 59Co is produced in stars through slow neutron capture processes and remains the predominant cobalt isotope on Earth. Small fractions of other cobalt isotopes can be produced by cosmic ray spallation, but they are typically unstable and transient.

Uses and applications stem largely from its natural abundance and magnetic properties. 59Co NMR spectroscopy is widely used in inorganic and materials chemistry to probe the electronic structure, oxidation state, geometry, and ligand environment of cobalt-containing compounds. In metallurgy, cobalt as an element contributes to the properties of alloys, magnets, and catalysts, with 59Co serving as a stable isotopic component in analytical and research contexts.

Safety considerations for cobalt and its compounds focus on toxicological effects from inhalation or ingestion, rather than radiological exposure, since 59Co is not radioactive. Proper handling and exposure controls are advised in industrial and laboratory settings.

See also: cobalt, isotope, 59Co NMR.