U-Pb concordia

U-Pb concordia is a method used by scientists to determine the age of rocks, especially old ones. It involves measuring the ratios of uranium isotopes (U-238 and U-235) that naturally decay into different lead isotopes over time. When the ratios of these isotopes in a mineral match a specific curve called the concordia, it indicates the sample's age is precisely determined and has remained undisturbed since formation. If the ratios don't align perfectly, it suggests some geological events or contamination occurred. The concordia curve helps experts identify the actual formation age of rocks with high accuracy.