Non-destructive pXRF for archaeological provenancing: obsidian and ceramics from the Near East

Abstract

The study of exchange networks in the Near East elucidates aspects of economic, social and political relations between past societies. For this region, obsidian and ceramics have been the key indicators for exchange. Non-destructive pXRF offers unique advantages for archaeological provenancing including non-destructive, in situ analysis. However, this technique presents significant methodological challenges for accurate and precise analysis, and provenance determination in the absence of geological reference materials. This thesis critically evaluates the application of non-destructive portable x-ray fluorescence (pXRF) analysis of obsidian and ceramic artefacts to archaeological provenancing. Experimental matrices are utilised for determining the parameters for accurate and precise analysis of archaeological materials. The archaeological utility of the developed methodology is then assessed in case studies of Chalcolithic earthenware ceramics, Chalcolithic obsidian and Byzantine lead glazed ceramics. In these case studies, the potential of legacy data-sets and archaeological artefacts of known provenance to provide useful comparative geochemical data for provenancing artefacts is evaluated. The results indicate that non-destructive pXRF has the potential to discriminate between compositional groups with high sensitivity when artefacts unamenable to analysis are omitted and appropriate methodology is applied during analyses. Although accurate and precise analyses can be achieved for both obsidian and ceramics, the relatively low number of diagnostic elements reported has greater implications for sourcing ceramics. Legacy datasets have the potential to accurately identify the provenance of obsidian artefacts whereas for ceramics, reference material that reflects contemporary manufacturing practices is required for accurate comparative analysis. Museum collections of artefacts have the potential to make significant contributions to reconstructing aspects of trade and exchange by expanding the scope of provenancing studies. These case studies into discrete aspects of trade and exchange networks in the Near East attest to the value of non-destructive pXRF in generating accurate and appropriate data to address archaeological questions. In this region, exchange networks linked to different artefact classes were largely disparate, and over time evolved in complexity and scale to encompass the entire Mediterranean.