Lead-207 is a stable isotope of the element lead, which has an atomic number of 82. It is produced through the radioactive decay of uranium-235 and thorium-232. Lead-207 has a mass number of 207 and is one of the isotopes used in various scientific applications, including radiometric dating. This isotope is significant in the uranium-lead dating method, which helps determine the age of geological samples. Lead-207 is non-radioactive, making it safe for use in laboratories and research. Its stability allows scientists to study the history of rocks and minerals over millions of years.