Chemical characterization of ancient potteries from Himera and Pestavecchia necropolis (Sicily, Italy) by Inductively Coupled Plasma–Optical Emission Spectrometry (ICP–OES)

Abstract

Thirty-eight samples of pottery were analyzed for determining chemical composition in order to establish their provenance. The potteries tested in the present research come from Himera and Pestavecchia archaeological sites. After digestion in microwave oven, the samples have been analyzed for fourteen minor elements (Ba, Cd, Co, Cr, Cu, Ga, Li, Mn, Ni, Pb, Sr, Ti, Tl, and Zn) and six major elements (Al, Ca, Fe, K, Mg, and Na). Chemical analysis was carried out by Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP–OES). The most abundant minor elements are Cr, Ba and Ni. Cr concentration ranged from 66 to 3635 mg kg−1, Ba concentration ranged from 388 to 2677 mg kg−1 and Ni concentration ranged from 35 to 1758 mg kg−1. The relative standard deviation (RSD) of the replicates on the concentrations of analyzed metals ranged from 0.07% to 14%. The aim of this study is to assign the local or non-local provenance of the examined potteries, in particular validating and clarifying archaeological hypothesis based on the simple visual examination and stylistic characterization of ceramic objects. Principal component analysis performed on the dataset, together with the application of cluster technique and non statistical analysis, allowed the identification of three main groups of samples and a lonely one (R 97). In particular, sample R 97 shows high Cr concentration (3635 mg kg−1) and high Ni concentration (1758 mg kg−1), typical of Corinthian pottery. The results of chemical analysis show that the stylistic features are not always sufficient to correctly identify the origin of a ceramic object.