Raw materials procurement strategies at the Ciota Ciara cave: new insight on land mobility in north-western Italy during Middle Palaeolithic

The importance of the Ciota Ciara cave for the understanding of the Middle Palaeolithic peopling of Piedmont (north-western Italy) is known since the 60s but it is just since 2009 that systematic and multidisciplinary archaeological excavations are ongoing at the site. In this region, studies about Palaeolithic are quite underdeveloped and the proposed research represents the first attempt to understand Middle Palaeolithic land mobility in the region. The lithic assemblage found is composed by 7046 artefacts and different raw materials are involved in the production of lithic artefacts. Vein quartz is the main exploited raw material in all the archaeological layers followed by spongolite, a local variety of chert, and by a better-quality grey/black flint. For these rocks the reduction sequences are complete while other raw materials are sporadically attested all along the sequence (opal, jasper and milonite) and probably exploited out of the site. Rhyolite and radiolarite are present in different proportions in all the archaeological levels and are represented almost exclusively by retouched tools and by small flakes belonging to the reshaping or re-sharpening of the tools’ edges. The proposed research focuses on the identification of the supply areas of lithic raw materials in order to define the land mobility of the human groups that inhabited the cave during Middle Palaeolithic. The study involves both local and allochthonous raw materials to understand the mobility range on a local and sub-regional scale. Starting from the idea of evolutionary chain, a specific methodology has been developed for vein quartz, aimed at the identification of the most probable secondary sources exploited. For all the raw materials, field works and lab analysis (stereomicroscope observations, Scanning Electron Microscopy and µ-XRF analysis) have been set up. The results obtained show that several local primary and secondary deposits were exploited, located at few hundred meters from the site. Vein quartz was collected in secondary deposits at the base of the mount while rhyolite comes from secondary deposits located at about 2 km in a straight line from the site. Radiolarite was instead collected within deposits located at distance between 20 and 30 km from the Ciota Ciara cave giving the chance to formulate reliable hypothesis on the seasonal mobility of the Middle Palaeolithic hunter-gatherers of the Ciota Ciara cave