The Method of Carbon-14 Technique Archaeologists rely on the various radiometric dating techniques- based on the radioactive properties of unstable chemical atoms to determine the age of the materials. In the biosphere carbon-14 is created by the collision of a neutron, exited by the cosmic ray collides with a nitrogen atom.

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 radiocarbon, which is unstable.

Carbon-14 isotope will undergo decay at an exponential rate to form the stable nitrogen-14. The following equation is used to determine the carbon-14 decay.

Thus by comparing the relative quantity of carbon -12 and carbon -14 in an organic matter excavated scientists can predict the age of the object (R. Where N is the current amount, N_o is the original amount, lambda is the proportionality constant for the growth rate (which is negative for decay), and t is the amount of time that has passed. Source: (Brain, 2014) The half-life of carbon-14 is 5730 years.