This study seeks to investigate long-term social and economic change from the perspective of production and exchange in a region with marked developmental changes in prehistory. First, major stages in south-central Andean prehistory have been widely discussed in the literature, including the transitions from foraging to food production, mobility to sedentism, egalitarianism to social ranking, and from low-level exchange to sustained interregional exchange. Should one not expect marked changes in the acquisition and production of obsidian that are correlated with these large scale prehistoric developments? For example, with the domestication of camelids and the emergence of llama caravans the costs in both time and labor in transporting weighty cargo, including obsidian nodules, must have dramatically decreased. Furthermore, with increased specialization one might expect merchant caravans or state-controlled interests to have emerged that benefit from the regional demand for obsidian. Complexities lurk behind each of these assumptions as these changes are largely co-evolutionary. Problems also lie in the very measures that are used to quantify changes in obsidian production, circulation, and consumption in the region.

Theoretical complications rest largely in three major issues; (1) the cross-cultural study of labor and value in economic anthropology, (2) associations between exchange and socio-political complexity, and (3) measures of prehistoric production that are both valid and practicable in the study of quarry areas. Each of these general issues will be addressed in turn below, and in the subsequent chapter (Ch. 3) the focus will be shifted to the south-central Andes.

Investigations using a close adherence to individual high-level theoretical approaches, particularly formal models of exchange and efficiency in production, were explored during the 1970s and 1980s in a number of obsidian quarry studies, most notably in the Mediterranean and in Mesoamerica. In these areas the regional trajectory benefits from distinct evolutionary changes like the development of highly efficient prismatic blades and well-documented mercantile traditions that perhaps conformed more closely to neoclassical economic cost-efficiency. Yet even in these areas, formal models encountered substantial difficulties in linking theoretical expectations with the breadth of regional exchange and in establishing empirical measures of control and efficiency beyond technical attributes of blade production. This study assumes a broader theoretical approach based primarily in finding correlates between evidence for prehispanic obsidian production and circulation and regional developments in economic organization and socio-political ranking. The theoretical issues presented here are linked to (1) evaluating the structure and level of independence of exchange networks and caravans, and (2) the degree of control exerted by household economies, aggrandizing individuals, and population centers prior to, and during, the Formative in the Lake Titicaca Region.