We present new data about the trace-element geochemistry of obsidian artifacts from archaeological sites located in the mixed Nothofagus and Austrocedrus forest of northwest Patagonia, Argentina. These data enlarge the available information in this field and allow us to discuss both the spatial distribution and the circulation of obsidian inside the forest and between this environment and both the steppes to the east and the Pacific coast to the west. We analyzed by ICP-MS the trace-element composition of 32 archaeological obsidian artifacts from seven sites located in the localities of El Manso, El Hoyo and Cholila. These data indicate north-south circulation of obsidian within the interior of the forest, and also east-west circulation over considerable distances between the steppes and the forest. No obsidian from sources in Chile has been found. Even though hunter-gatherers began to inhabit the Andean Patagonian forest in the Early Holocene, previous studies have not recorded the use of obsidian inside the forest environment until Late Holocene when the most intense human occupation of these spaces occurred. The new data presented here extends the temporal discussion of the use of obsidian in the forest back into the Early Holocene.

Compositional analyses performed on obsidian pieces, turquoise beads and metallic artefacts from Mocha Island allow us to propose a high mobility scenario for these goods for the last 1000 years in Southern Chile. These analyses lead us to hypothesize about the connections with areas such as the Coastal Range in Araucanía (35 km), central Neuquén in Argentina(390 km), and the Bolivian Altiplano/Argentinian Northwest (1900 km). The presence of these goods in Mocha Island and Southern Chile would be part of the deep social transformations undergone by the societies that inhabited these territories toward the end of the first millennium AD, leading to the formation of the El Vergel complex.

In this paper, we examine the strategies of supply, exploitation, circulation and consumption of the obsidian found in sites from the archaeological localities of La María and Cerro Tres Tetas (Central Plateau of Santa Cruz province, Argentina). Technomorphologic, functional and geochemical analyses of the obsidian remains from these localities were carried out. Results show that obsidian comes from Pampa del Asador a source located over 125 km from the sites. Two chronological moments in the exploitation of this raw material were identified with an increase in consumption over time. During the Final Pleistocene/Early Holocene, obsidian was not a significant resource in the technological organization. Production sequences indicate that tools may have arrived already manufactured to the sites. In contrast, in the Middle and Late Holocene, cores and/or nodules were brought to the localities. Production strategies are similar to the ones recorded for local raw materials. There is no evidence to indicate that obsidian was a more valued resource than local rocks. We cannot ascertain that obsidian acquisition was part of a sporadic exploitation strategy from the source region. We believe that this raw material was obtained in mobility circuits and from intergroup contact.