both decaying by electron capture, are ²⁰⁵Pb with a half-life of 17.0 million years and ²⁰²Pb with a half-life of 52,500 years. A shorter-lived naturally occurring radioisotope, ²¹⁰Pb with a half-life of 22.2 years, is useful for studying the sedimentation chronology of environmental samples on time scales shorter than 100 years.

The heaviest stable isotope, ²⁰⁸Pb, belongs to this element. (The more massive ²⁰⁹Bi,