The analysis of Italian Sigillata potters' stamps using Dual Energy Computed Tomography (DECT) and X-ray imaging

Dual Energy Computed Tomography (DECT) and conventional X-ray imaging are employed in this study to investigate stamped Italian Sigillata vessels excavated at the Roman site of Carsulae in Umbria, Italy. DECT and conventional X-ray imaging were chosen for this investigation because they are non-destructive techniques, and permission to examine the material was given only on the condition that the ceramics were not physically altered.

The study aims to define the composition of the ceramic fabrics and seeks to identify the manufacturing practices employed by Italian Sigillata workshops.

The results indicate that although the clays used by Italian Sigillata producers in northern Italy were similar in composition overall, the preparation of clay varied considerably between manufacturing centres and individual potters.

Importantly, the investigation also reveals that the composition of the ceramic fabric is not always uniform throughout each vessel. This result holds significant implications for traditional ceramic studies, where samples are routinely removed from specific areas of vessels for conventional compositional analyses.