Application of the ‘no fool's clock’ to dating the Mukodek gold field, Siberia, Russia

The 40Ar/39Ar dating method on pyrite-encapsulated sericite, known as the ‘no fool's clock’, is promising for bracketing gold ore formation processes. Using this dating technique we show that gold mineralization at the Mukodek gold field, Siberia, Russia took place in the Late Paleozoic at the time of emplacement of the Angara–Vitim granitoid magmas. Late Paleozoic magmatism, however, was not the source of gold. It was the source of heat and fluids that preconcentrated already available gold within alteration zones and hydrothermal veins.