zinc64

Zinc-64, or 64Zn, is a stable isotope of the element zinc (atomic number 30) with a mass number of 64. It is non-radioactive and occurs naturally as part of zinc metal and zinc-bearing minerals.

It is the most abundant stable zinc isotope, making up about 49–50% of naturally occurring zinc. Other stable isotopes of zinc include 66Zn, 67Zn, 68Zn and 70Zn, with their relative abundances varying by ore and geographic source. As a result, natural zinc presents a characteristic isotopic composition used in scientific analyses.

Because of its stability and prevalence, 64Zn is widely used in scientific analyses as a standard for zinc isotope-ratio measurements and as a tracer in biochemical and environmental studies. Analytical techniques such as isotope ratio mass spectrometry (IRMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) frequently report 64Zn in relation to other zinc isotopes for tracing processes and studying provenance.

In nature, zinc isotopes including 64Zn arise from stellar nucleosynthesis and subsequent mixing in the galaxy, with additional minor production by cosmic ray spallation. In practical terms, 64Zn is considered when calibrating zinc measurements and interpreting isotopic data in geology, biology, and materials science.