Simple definition of carbon dating
Most carbon consists of the isotopes carbon 12 and carbon 13, which are very stable.
A very small percentage of carbon, however, consists of the isotope carbon 14, or , which is unstable.
Notice that the nitrogen-14 atom is recreated and goes back into the cycle.
Because the ratio of carbon 12 to carbon 14 present in all living organisms is the same, and because the decay rate of carbon 14 is constant, the length of time that has passed since an organism has died can be calculated by comparing the ratio of carbon 12 to carbon 14 in its remains to the known ratio in living organisms.
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Try it risk-free Ever wondered how scientists know the age of old bones in an ancient site or how old a scrap of linen is?
In the late 1940s, American chemist Willard Libby developed a method for determining when the death of an organism had occurred.
He first noted that the cells of all living things contain atoms taken in from the organism's environment, including carbon; all organic compounds contain carbon.