Reliability of a new X-ray analytical microscope in archaeological research

In this report we assess both the reliability and sensitivity of a new X-ray Analytical Microscope (XAM) in specific archaeological studies. The instrument's precision is measured here by its ability to repeatedly produce similar data each time it analyzes the same sample. The accuracy, sensitivity and detection limits of the XAM were evaluated through the quantification of spectra acquired from certified reference materials (CRM), while potsherd identification was assessed by analyzing several potsherds found at different archaeological sites, then correlating their chemical compositions to determine compatibility and possible grouping. Repeatability standard deviation percentages for relative intensity values ranged between 1% and 4% for major elements, while the system's sensitivity for detecting trace elements was in the 50-100 ppm range. Quantification accuracy was excellent with a fitting factor of 0.98 between measured and certified element concentrations. Archaeological potsherds were clearly distinguished according to their elemental compositions, and grouped using bivariate graphs. (C) 2012 Elsevier Ltd. All rights reserved.