UC Santa Barbara

Regional studies of obsidian artifacts in the south-central Andes have shown that over 90% of the analyzed artifacts from the Lake Titicaca Basin belong to a single geochemical obsidian type. A decade ago researchers identified the geological origin of this obsidian type as the Chivay / Cotallalli source, located 180km west of Lake Titicaca above the Colca valley in Arequipa at 71.5355° S, 15.6423° W (WGS84), and at 4972 meters above sea level. This research project focused on the obsidian source and adjacent lands within one day’s travel from the source. The project included a 33 km2 survey, 8 test units, and in-depth lithic attribute analysis. Mobile GIS (Arcpad) was used extensively during survey. A substantial quarry pit and an obsidian workshop were examined closely, as were consumption sites in nearby areas. The results of this study found that the earliest diagnostic materials at the source date to the Middle Archaic (8000 – 6000 BCE) and that intensification of obsidian production occurred earlier than previously recognized, at circa 3300 BCE Increased obsidian production appears to have been focused on the acquisition of large (> 20cm) and homogeneous obsidian nodules, although the formal tools produced with obsidian were predominantly small projectile points. It is argued that the acquisition of large, homogenous nodules was prioritized because the production potential of large nodules was highest, and because obsidian was associated with competitive display among early aggrandizers. The timing and economic associations of obsidian production and circulation suggest that the possession of large obsidian pieces in the Titicaca Basin was a demonstration of social connections to distant resources, and to regional trade networks that emerged with regularized camelid caravan transport networks. Obsidian artifacts were not inherently “prestige goods”; rather, it is suggested here that obsidian was the least-perishable of a number of cultural goods distributed by an expanding network of caravans that linked communities in the region. The acquisition and consumption of these cultural goods was a demonstration of economic connections and cultural influence during the dynamic period of incipient social inequality between the Terminal Archaic (3300–2000 BCE) through the Middle Formative (1300–500 BCE).