PRELIMINARY RESULTS OF A PXRF ANALYSIS ON CERAMICS FROM THE EASTERN MEDITERRANEAN REGION

116 ceramic pottery sherds were analyzed using a Niton XL3t 900S GOLDD portable x-ray fluorimeter (pXRF) at the Ephorate of Antiquities of the Dodecanese (EAD) in Rhodes, Greece. PXRF is a non-destructive method for analyzing ceramics, but is currently not a standalone method for determining the provenance of such artifacts. Geographical origins for 14 of the samples were verified by faculty of the EAD at 12 locations within the Eastern Mediterranean region. One goal of the project is to compare the elemental compostion, as determined by pXRF analysis, of the 102 unsourced ceramics to those whose origins are known. Another goal of the project is to create a digital database for current and future pXRF analyses.

Following 4 earlier studies in which pXRF technology was used to analyze ceramics and/or obsidian artifacts, the ceramics analyzed using pXRF in this study were compared by plotting their concentrations, or ratios of concentrations (in parts per million), on 7 x-y graphs. Elements compared on the graphs include: Sr/Rb vs. Y/Ba; Sr/Ba vs. Nb/Rb; Y vs. Sr/Y; Rb/Sr vs. Zr/Y; Nb/Zr vs. Nb/Sr; Nb vs. Zr; Sr vs. Zr.

The current digital database consists of 141 PDF datasheets for each of the 116 ceramics analyzed with the pXRf in this study and an additional 25 datasheets for future analyses. Every digital datasheet contains the following information about its respective ceramic sample: 2 sample IDs (one analysis specific and one EAD specific), photo ID, origin (if known), calibration standard ID, sample description, photograph of the sample, graph of the analysis (KeV vs. Counts/Sec.), and a table with 22 elements derived from the pXRF analysis (i.e. Ba, Nb, Zr, Sr, Rb, As, Pb, Zn, Cu, Fe, Mn, Cr, V, Ti, Ca, K, Al, P, Si, S, Mg, Y) and their associated error values.

Future work will involve a comparison of pXRF results from ceramics used in this study to the results derived from the same samples using other analytical methods by researchers at the EAD, e.g. neutron activation analysis and petrographic thin-section analysis. The results from this study will also be compared to those from a pXRF analysis conducted in 2014 with the same instrument on ceramics from Israel.