One of the most widely used is potassium–argon dating (K–Ar dating).
By measuring the carbon-14 in organic material, scientists can determine the date of death of the organic matter in an artifact or ecofact.
Absolute dating provides a numerical age or range in contrast with relative dating which places events in order without any measure of the age between events.
In archaeology, absolute dating is usually based on the physical, chemical, and life properties of the materials of artifacts, buildings, or other items that have been modified by humans and by historical associations with materials with known dates (coins and written history).
This technique is based on the principle that all objects absorb radiation from the environment.
This process frees electrons within minerals that remain caught within the item.
It cannot be used to accurately date a site on its own.