Take a walk on the clay-site – tracing raw materials through experimental archaeometry

Suitable raw material is the basis for every ceramic object. In order to study the artisanal choices and factors associated with the selection of clays for Bronze Age ceramic production a raw-material survey has been carried out near the excavation site of Grutt’i Acqua on the peninsula of Sant'Antioco (Sardinia). This project is characterized by a transdisciplinary combination of experimental archaeology and mineralogical material science analysis - carried out in a cooperation between ArchaeoLytics and the Institute for Archaeological Studies of the Ruhr-University Bochum.

Nineteen clay-rich sediments have been collected and processed to examine their suitability to produce pottery according to local Bronze Age techniques and diagnostic vessel shapes. Based on standardized test-tiles the dry- and fire-shrinkage as well as the color-variations have been recorded for firing-experiments at 600 and 900°C. Ten samples out of this series have been selected for further investigations including polarizing microscopy, XRD and XRF. Preliminary comparisons with local Bronze Age shards show clear distinguishing features, allowing a solid provenance study. In addition, our field experiences, the in-situ processing of raw materials and the X-Ray data provide us with a more profound and broader understanding of the local Bronze Age pottery in the area of Grutt’i Acqua.