Micro-PIXE/PIGE analysis of Palaeolithic mammoth ivory: Potential chemical markers of provenance and relative dating

Micro-Proton Induced X-ray and Gamma-ray Emission (micro-PIXE/PIGE) provide non-destructive methods for the evaluation of the major, minor and trace element compositions of archaeological material. The current study applies micro-PIXE/PIGE analysis to mammoth ivory artefacts from four Palaeolithic sites (Abri Castanet, Vogelherd Cave, Grottes de la Verpillière I and II) in France and Germany in order to assess the effectiveness of this approach to material older than 30,000 y BP. It has thus far not been established whether such methods of analysis can yield results of scientific and archaeological interest on ivory material that has undergone such extended periods of diagenesis. This approach evaluated preservation state in terms of mean elemental concentrations (Mg vs. Ca) and a comparative assessment of F-content as an indication of relative burial time. The results also indicate that analysis of trace elements (Sr, Zn, Br) can provide chemical markers of archaeological provenance. The results of this study are compared to data in the existing database established by the same methods of analysis on ivory objects from several different time periods and archaeological sources. The implications of these results for the study of archaeological ivories from Palaeolithic contexts are discussed.