single-stage lead

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single-stage lead Common lead (Pb) removed at a particular time from a single, constantly evolving, uranium—thorium—lead environment. It can be used to provide the basis for the common-lead method of dating (see LEAD-LEAD DATING). After the removal of this lead in solution and its deposition as a lead ore (such as galena), it is then assumed not to have been altered in isotopic composition by the further addition of radiogenic products.