They can also use Lichens to age rocks in many ways to see how long something has been around.'
It is called lichenometry I first read about it years ago.
https://www.google.com/url?sa=t&rct=...rg0DACz1zmZuIA
It always wears on me when people think carbon dating is the only method used to tell the age of something.
There are many ways.
When flint is chipped it starts growing a layer on it.
They can tell by the thickness of the layer approximately how long ago the flint was chipped to make the spear point.
Worth