Obsidian Economy in the Rio Saboccu Open-Air Early Neolithic Site (Sardinia, Italy)

Integrated provenance/typo-technologic/chaines operatoires studies on obsidians from Early Neolithic (EN) assemblages are still quite exceptional in the western Mediterranean region. The Rio Saboccu S1-S2 EN dwelling structures (Central-western Sardinia) 14C dated to the last three centuries of the VIth millennium BC provided us with an opportunity to apply such an approach. A comprehensive provenance study of its 1.114 obsidian artefacts was realized through a combined visual/instrumental approach. Elemental compositions were determined mostly by ion beam analysis (PIXE) and by electron microprobe (SEM-EDS). The S1-S2 structures are situated inside the so-called supply zone of the Monte Arci volcanic complex. A technological analysis of the implements revealed a non-opportunistic behaviour in relation to obsidian procurement among the four (SA, SB1, SB2, SC) Monte Arci types locally available in various contexts (from primary to secondary sources). A comparison with other Sardinian EN sites suggests that the human groups settled near the Monte Arci sources might have acted as a ‘filter’ in the first stages of the diffusion of obsidians in Sardinia and possibly elsewhere in the northern Tyrrhenian area.