88Sr

88Sr is a stable isotope of the element strontium, with mass number 88, atomic number 38, and 50 neutrons. It is the most abundant strontium isotope in natural samples, comprising about 82.6% of natural strontium. The atomic mass of 88Sr is about 87.9056 atomic mass units. Like other stable isotopes, 88Sr does not decay radioactively under normal conditions.

In nuclear terms, 88Sr has a closed neutron shell at N = 50, which contributes to its relative stability compared with some neighboring isotopes. Its abundance and stability make it a major component of natural strontium encountered in minerals and rocks.

88Sr occurs widely in the Earth's crust as part of common strontium minerals, including celestite (SrSO4) and strontianite (SrCO3). Its presence, together with other stable isotopes such as 84Sr, 86Sr, and 87Sr, is exploited in geochemical and geochronological studies that trace sourcing, weathering, and planetary differentiation.

Analytical applications typically emphasize the ratios among strontium isotopes, especially 87Sr/86Sr, for provenance and dating studies. While 88Sr is not the ratio of primary interest in geochronology, it appears in mass spectrometric measurements as part of the isotopic suite and can aid in calibration, correction for mass bias, and quality control in isotope ratio analyses.

Overall, 88Sr’s predominance in natural strontium and its stable nature make it a fundamental component in studies of geological and environmental processes, as well as in instrument calibration for isotope measurements.