Chemical dating techniques
Thus dating that particular tree does not necessarily indicate when the fire burned or the structure was built.
For this reason, many archaeologists prefer to use samples from short-lived plants for radiocarbon dating.
K–Ar dating was used to calibrate the geomagnetic polarity time scale.
Cosmic radiation entering the earth’s atmosphere produces carbon-14, and plants take in carbon-14 as they fix carbon dioxide.
One of the most widely used is potassium–argon dating (K–Ar dating).
Potassium-40 is a radioactive isotope of potassium that decays into argon-40.
It cannot be used to accurately date a site on its own.
However, it can be used to confirm the antiquity of an item.