Radiogenic isotopes are powerful tracers that are being increasingly used in ore geology to determine two critical pieces of information namely (i) the source (s) of the ore constituents, and (ii) the timing of mineralization. These data enable us to understand the processes that move, distribute, and mix materials in various Earth system reservoirs and also provides crucial temporal constraints on their timescales and durations. Although cross-cutting relationships can provide accurate constraints on relative time, our understanding of the spatial scale and temporal variability of ore genetic processes is incomplete without a sense of absolute time. Also, ore-forming processes are generally spread over multiple pulses or episodes and the ore environments are characterized by chemical and physical disequilibrium from nanometre to kilometer scale. Radiometric age dating provides a means of quantifying the rates of ore genetic processes and permits their absolute correlation on scales from individual samples to those of mines, metallogenic provinces, and continents. The technique involves the measurement and interpretation of the changes in the isotope composition of elements brought about by spontaneous decay of certain radioactive nuclides.