Liquid scintillation counting is another radiocarbon dating technique that was popular in the 1960s.In this method, the sample is in liquid form and a scintillator is added.American physical chemist Willard Libby led a team of scientists in the post World War II era to develop a method that measures radiocarbon activity.
This scintillator produces a flash of light when it interacts with a beta particle.
A vial with a sample is passed between two photomultipliers, and only when both devices register the flash of light that a count is made.
Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed.
The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
The method does not count beta particles but the number of carbon atoms present in the sample and the proportion of the isotopes.