[ELI5] How do archaeologists know that what they found was an actual 1.3 million year old axe and not just a weird shaped rock?

Question

Prompted by this article [https://www.aljazeera.com/news/2021/7/28/archaeologists-in-morocco-announce-major-stone-age-find](https://www.aljazeera.com/news/2021/7/28/archaeologists-in-morocco-announce-major-stone-age-find)

In: Earth Science

Answer 1

The age of the soil at the site it was buried in can be found by carbon dating, similar methods can be used to confirm the age at which the rock became chipped as chemical changes may occur at the surface.