Hey Justin: When you get just West of Weatherford and cross the Brazos river, there is some chert in there. Not big pieces but nice stuff if ya cook it. The crossing at I 20 is sandy, not many rocks - You'd have to take hwy 4 north out of Palo Pinto to dark valley. Pretty good little diversion off your trail but there's flint in there. Only others I can think of are all a good ways south of your route, like around Junction, San Angelo - down in that country. Lots of perd..