How are carbon isotopes used in carbon dating
In order to date the artifact, the amount of Carbon-14 is compared to the amount of Carbon-12 (the stable form of carbon) to determine how much radiocarbon has decayed.
The ratio of carbon-12 to carbon-14 is the same in all living things.
To measure the amount of radiocarbon left in a artifact, scientists burn a small piece to convert it into carbon dioxide gas.
Radiation counters are used to detect the electrons given off by decaying Carbon-14 as it turns into nitrogen.
Renfrew (1973) called it 'the radiocarbon revolution' in describing its impact upon the human sciences.
There are three principal isotopes of carbon which occur naturally - C12, C13 (both stable) and C14 (unstable or radioactive).
These isotopes are present in the following amounts C12 - 98.89%, C13 - 1.11% and C14 - 0.00000000010%.
By measuring the ratio of carbon-12 to carbon-14 in the sample and comparing it to the ratio in a living organism, it is possible to determine the age of the artifact.
"Everything which has come down to us from heathendom is wrapped in a thick fog; it belongs to a space of time we cannot measure.