Author name: Holly Stein

Rhenium-osmium geochronology of sulfides and its Os tracer accompaniment have taken their place among geochronometers, although the journey was not without doubters and disparagers. This review highlights several historical hurdles overcome in dating sulfides. The opening act was the debut of molybdenite, which provided an accessible radiometric clock and early insight into the accuracy of the ¹⁸⁷Re decay constant. Once controversies surrounding newly minted and game-changing Re-Os molybdenite ages died down, the door flung wide open to begin dating other sulfides, most notably, arsenopyrite and pyrite. Applications sprinted from the ore geology community to constraining the timing of important events, from Earth’s oxygenation to the amalgamation of tectonic terranes. The power of Re-Os sulfide dating in crustal environments was unleashed.