As explained below, the radiocarbon date tells us when the organism was alive (not when the material was used).This fact should always be remembered when using radiocarbon dates.
The carbon-14 isotope would vanish from Earth's atmosphere in less than a million years were it not for the constant influx of cosmic rays interacting with molecules of nitrogen (NFigure 1: Diagram of the formation of carbon-14 (forward), the decay of carbon-14 (reverse).
Carbon-14 is constantly be generated in the atmosphere and cycled through the carbon and nitrogen cycles.
The dating process is always designed to try to extract the carbon from a sample which is most representative of the original organism.
In general it is always better to date a properly identified single entity (such as a cereal grain or an identified bone) rather than a mixture of unidentified organic remains.
Common materials for radiocarbon dating are: The radiocarbon formed in the upper atmosphere is mostly in the form of carbon dioxide. Because the carbon present in a plant comes from the atmosphere in this way, the radio of radiocarbon to stable carbon in the plant is virtually the same as that in the atmosphere.
Plant eating animals (herbivores and omnivores) get their carbon by eating plants.
Radiocarbon dating is one of the most widely used scientific dating methods in archaeology and environmental science.
It can be applied to most organic materials and spans dates from a few hundred years ago right back to about 50,000 years ago - about when modern humans were first entering Europe.
Radiocarbon dating (usually referred to simply as carbon-14 dating) is a radiometric dating method.
It uses the naturally occurring radioisotope carbon-14 (14C) to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years old. Carbon-14 has a relatively short half-life of 5,730 years, meaning that the fraction of carbon-14 in a sample is halved over the course of 5,730 years due to radioactive decay to nitrogen-14.
From this science, we are able to approximate the date at which the organism were living on Earth.