"TEXAS LITHIC SOURCES" by Walter Williams, originally published in Texas Cache Magazine Volume 23 #4, 2020.
Keyword search terms: lithic sources, material, flint, chert, silica, callahan divide, darl, eastland, quarry, alibates, mallouf, edwards plateau, baird, camp barkeley, basalt, cryptocrystalline, rhyolite, granitic, caracara knife, welded tuff, mudstone, obsidian, duran, scallorn, guerrero, jumano, gemstone, jasper, agate, big bend, walter williams