What is the ancient process of making paint and the purpose?

What is the ancient process of making paint and the purpose?
first, you grind soft minerals with a stone, or hand axe.
Second, you mix it with animal fat
Finally, you put the mixture into a bowel, and paint.
The purpose? Easy, you want to make your own paint because your culture makes everything by themselves, not to waste money on cheap stores, or your a caveman that discovered time travel and transported yourself like millions of years to get to the future, which in our point of view, now, to get some modern paint. :)