Isotope fractionation between galena and pyrite and between pyrite and elemental sulfur

Abstract

Sulfur isotope fractionation between pyrite and galena and between pyrite and elemental sulfur was investigated. Isotope equilibrium was not achieved in 120 days at 400°C and 500°C, nor in 40 days at 600°C. Slow diffusion of sulfur isotopes in pyrite and the isotopic inhomogeneity of the pyrite crystals are probably responsible. By the techniques used so far, isotope equilibrium in systems containing pyrite cannot be reached in a reasonable amount of time at the temperatures investigated. © 1971.