Not sure what you are asking. The stone age way of making paint is to find some place where the ground has a weird colour, dig it up, clean it and you have a pigment.

Even to this day many of our paint pigments are mined this way. Red/yellow ochre, umber, sienna.

If what you are asking is the dirt in question geologically speaking a soil? Sometimes, sometimes not. It can be a sediment or a regolith too. But in the more general laymen sense callig any dirt from the ground a soil is not too mistaken.