Sardinian Obsidian Circulation and Early Maritime Navigation in the Neolithic as Shown Through Social Network Analysis

ABSTRACT: Scholars typically argue that cultural interaction between the West Mediterranean islands of Sardinia and Corsica and the European mainland took place through the Tuscan Archipelago, via such intermediary islands as Elba and Pianosa. This path is posited as the prime route in and out of these islands for both people and objects throughout prehistory largely due to the belief that early—pre-sail—seafarers would have wished to avoid more treacherous open-sea voyages. This article tests this hypothesis using social network analysis (SNA) to identify the strengths of inter-site relationships through time based on the relative proportions of West Mediterranean obsidian raw materials at 79 Neolithic sites dating from the sixth to fourth millennia BC. We argue that similar patterns of obsidian consumption reflect similar procurement mechanisms and the likelihood of more frequent interactions between the people of these communities. As such, it becomes possible to reconstruct the relationships that mediated the distribution of obsidian across the landscape. Contrary to previous interpretations highlighting the role of Elba and Pianosa in the exchange of obsidian from the geological sources of Sardinia along the coast to northern Italy and France, our results suggest that obsidian also took a more direct open-sea path upwards of 200 km from Corsica to the coastal regions of Provence and Languedoc in southern France. These results are contextualized within broader patterns of obsidian circulation and use and have important implications for debates surrounding Neolithic obsidian procurement, exchange spheres, and early maritime navigation.