Automated SEM-EDS pottery classification based on minero-chemical quantitative parameters: An application on ancient Greek pottery from Adrano (NE Sicily, Italy)

A new SEM-EDS procedure for ancient ceramic classification, based on the automated acquisition and the semiautomated processing of multi-elemental X-ray maps, is described. Based on the detection of each aplastic inclusion, the procedure allows to simultaneously obtain a quantitative evaluation of both the inclusion mineral-chemical composition and the ceramic matrix chemical composition. The two data sets can individually or jointly be subjected to statistical methods. The proposed protocol was applied on a set of 22 samples of black glaze pottery from Adrano (north-eastern Sicily), Hellenistic age (4th to 2nd centuries B.C.). Two main groups emerged from the application of the procedure, mainly distinguished for their quartz-feldspars versus calcium-aluminosilicate relative abundance as the inclusion mineral-chemical composition is concerned and for their matrix SiO2 versus CaO. The classification based on the inclusion mineral-chemical data obtained with the proposed method mirrors the results from the traditional OM observation, but when the two data sets are simultaneously considered, a subtler differentiation is observed with the separation of one of the groups in two subgroups, allowing to refine the partition.