But it gave to archaeology a scientific sophistication many in the field had been desperately seeking. Estimates of antiquity were no longer enough, for now there were real numbers. The local boundaries of prehistory became blurred. Chronologies could be figured both for single sites and for multiple sites around the world, allowing new patterns and links to emerge. Radiocarbon dating verified and refined cultural chronologies based on pottery, tools, and cultural developments.
Isotopes are atomic variants of the same element that differ in the number of neutrons they contain.
Almost all carbon is C-12, with six protons and six neutrons. Produced by atmospheric interactions with cosmic rays from the sun, a C-14 atom has six protons, but contains eight neutrons. That means half the C-14 atoms in a sample decay in 5,730 years, half of those that remain disappear in another 5,730 years, and so on. Libby was beginning to see the promise of all this when World War II put the research on hold. Life on Earth is based on carbon, which exists in many forms.