Lead-208 is a stable isotope of the element lead, which has an atomic number of 82. It is one of the end products of the radioactive decay of uranium and thorium. Lead-208 has a mass number of 208, meaning it contains 126 neutrons and 82 protons in its nucleus. This isotope is significant in various fields, including nuclear physics and geochronology. It is often used in studies related to the age of rocks and minerals, as well as in the investigation of nuclear reactions. Lead-208 is non-radioactive, making it safe for many applications.