Select formal tools from the Dona Ana County Airport site; a: obsidian preform and uniface with drawings of preform; b: obsidian projectile points; c: Archaic dart point, extensively reworked projectile point, and unifacial tool. Nearly 64% of the site’s chipped-stone artifact assemblage is made of obsidian. This is unusually high for the Trans-Pecos, where obsidian rarely exceeds 10% of a lithic assemblage, even at sites directly adjacent to obsidian-bearing gravel deposits. Photo from Miller 2001, Fig. 10.