New results from sourcing the Early Neolithic obsidian artefacts from Pollera Cave (Liguria, NW Italy)

Résumé En

The authors present the results of new chemical characterizations of Early Neolithic obsidian artefacts yielded by the excavations carried out at Cave Pollera in 1971-1973. We analysed four artefacts from the Impresso-Cardial layer III, level XXII. The finds had already been analysed by neutron activation (INAA) at the end of the 1970s during Lawrence H. Barfield’s pioneering obsidian circulation research in northern Italy. The scope of the new characterizations was to solve some problems raised from previous publications (i.e. 3 artefacts, one of which was generically attributed to the Impressed Ware Culture, the second from the XXII level and the third from level XVII, published by Williams-Thorpe and others in 1979, whilst G. Odetti in her 1991 paper reported 4 artefacts, all from level XXII). This contradictory information did not allow us to identify each analysed artefact and attribute it to its original source (at that time determined as Lipari and Sardinia). Moreover, the presence of obsidian imports from Lipari in the upper Tyrrhenian Sea region during the Early Neolithic does not agree with more recent data obtained from obsidian samples characterised from the neighbouring Arene Candide Cave. Therefore, the four artefacts have been re-analysed at IRAMAT-CRP2A by non-destructive methods (PIXE at CENBG [AIFIRA platform] and EDXRF). The new results exclude the presence of Lipari obsidian from the Early Neolithic Pollera deposits. In contrast, they outline a picture more coherent with that obtained from the analyses of coeval obsidian samples collected from sites located in the Liguro-Provençal Alpine arc. Finally, this research pinpoints to the need of reviewing the characterizations published during the first pioneering archaeometric obsidian studies with more precise sourcing databases and methods, to be applied especially when they seem to contrast with a new, more reliable archaeological evidence.