Over the second half-life, of the atoms remaining decay, which leaves of the original quantity, and so on.In other words, the change in numbers of atoms follows a geometric scale as illustrated by the graph below.other carbon isotopes in the same ratio as exists in the atmosphere.However, human beings love to see factual precision, and we want to know how old something is.Please remember that all dating methods, even those termed "absolute," are subject to margins of error. That is a very small amount of possible error range. Modern studies almost always use two or more methods to confirm dating work and to build confidence in the results obtained.
The successive layers of rock represent successive intervals of time.
Luminescence dating is a method to determine how long since something was exposed to sunlight.
In the case of our enquiry at Zagora, we want to know when a wall was built. Our archaeologists can generally tell an old wall from a recently built wall even if the building method, eg, stacking stones, is the same.
So it was wondered whether this wall may have been built in antiquity at the base of another access path to the settlement.
The only way to determine this was with scientific testing.