A REGIONAL ASSESSMENT OF OBSIDIAN USE IN THE POSTCLASSIC AZTATLAN TRADITION

Abstract

Abstract Of the many items that were traded throughout the Postclassic (A.D. 850/900–1350) Aztatlan network, obsidian was perhaps the most prevalent. In this study, large assemblages of obsidian from five Aztatlan centers on the coastal plain are discussed: San Felipe Aztatan, Chacalilla, Amapa, Coamiles, and Peñitas. In total, over 12,000 obsidian artifacts were analyzed macroscopically and through handheld portable X-ray fluorescence. The results of these analyses illustrate regional patterns of obsidian use that appear consistent across the coastal plain. Generally, only three obsidian sources were used with frequency. The most proximal source was utilized for generalized reduction and probably acquired directly, while more distant obsidians from the Jalisco highlands are commonly found in the form of prismatic blades. These trends in obsidian use indicate an increase in source diversity concurrent with the development of the Aztatlan trade networks despite the local availability of quality obsidians. Finally, synchronic patterns of source distribution further indicate that sources were unevenly distributed as certain individuals likely had greater access to imported blades. In conclusion, this large study provides a regional perspective of obsidian use in Western Mexico on the coastal plain and showcases the pervasiveness of the obsidian trade during the Postclassic.