8.2. Review of major findings

Summarizing the results presented in Chapters 6 and 7, a number of changes in obsidian procurement at the Chivay source correspond to changes recognized regionally in south-central Andean development. While the activities at the Chivay source area did not exactly meet the expectations of the project that were implied by patterns of regional consumption data. The differences between the expectations and the results of the Upper Colca project are informative, and these differences will be highlighted in the text. The differences appear to be largely the result of a historical bias in research, in that there has been a predominant focus on the more socially complex, later episodes in Andean prehistory. For example, obsidian has been found in many ceremonial Tiwanaku contexts and in the Tiwanaku core area such that some investigators in the heartland area argue that the Chivay source was state-controlled (Giesso 2003). Yet, in numerous studies in the Colca region, and this study of the Chivay source in particular, archaeologists have yet to find definitively Tiwanaku artifacts in the Colca area. Contrasting with this lack of evidence from the Tiwanaku period, consider the evidence from earlier periods: the Terminal Archaic and Early Formative. While relatively few sites have been excavated that date to the Archaic / Formative transition in the south-central Andean highlands, the evidence from the Chivay source shows that obsidian production intensified during that time. Indeed, a review of the little evidence available from Terminal Archaic and Early Formative sites in the adjacent consumption zone indicates a spike in obsidian consumption during that time.

In other words, archaeologists in the south-central highlands have historically focused on late prehispanic complex polities, and today the legacy of data from excavations aimed at regional centers has biased the overall picture of obsidian consumption towards the later Prehispanic period. While there were major social and economic changes underway in the third millennium BC, the findings here reveal that obsidian was one of the earlier materials to show a distinct increase in production and circulation in the south-central Andes.