Diachronic changes evident from the 2003 testing at the workshop suggest that shifts in production occurred that were consistent with the development and decline of an obsidian production system responding to the demands of regional consumption. It can be inferred from changing flaked stone artifacts at the workshop that a local production regime was replaced with an approach maximizing flake blanks for export that persisted for a time and, subsequently, shifted into biface production strategy, prior to reverting to a local production. This sequence of events occurs in the Terminal Archaic and Early Formative just as obsidian frequencies regionally reach their apex (e.g., at Qillqatani, see Figure 3-7). The evidence of these shifts appear in retouched artifacts, in cores, and in the changing morphology of complete flakes at the workshop test pit.

This in depth analysis involves an investigation of diachronic change in three separate groups of lithic artifacts. First, retouched flakes are briefly compared with bifaces. Next, multivariate analysis is used on cores to investigate changes across time. Finally, saving the best for last, the attribute analysis for 1063 complete flakes from the test unit is presented that reveals changes in reduction strategies and complementing the evidence from cores, bifaces, and retouched flakes.