Radiocarbon dating works by comparing the three different isotopes of carbon. Isotopes of a particular element have the same number of protons in their nucleus, but different numbers of neutrons. This means that although they are very similar chemically, they have different masses.
How do you read carbon dates?
0:522:10How Does Radiocarbon Dating Work? - Instant Egghead #28 YouTubeStart of suggested clipEnd of suggested clipAfter one half-life the animal will have about half the amount of carbon-14 it started with afterMoreAfter one half-life the animal will have about half the amount of carbon-14 it started with after another half-life it will have about a quarter.
How do you measure carbon-14?
There are three principal techniques used to measure carbon 14 content of any given sample— gas proportional counting, liquid scintillation counting, and accelerator mass spectrometry. Gas proportional counting is a conventional radiometric dating technique that counts the beta particles emitted by a given sample.