Research on Painted Pebbles of Mas-D'Azil: History and Modern Phase

The Dresden collection of painted pebbles of Mas d’Azil can be traced back to an acquisition of the Royal Geology and Mineralogy Museum directly from the excavator E. Piette in 1899. This exact record of provenience indicates that they might be authentic archaeological artefacts from this site compared to a vast number of forgeries that entered other collections probably by later acquisition as a result of growing interest towards prehistoric art at the turn of the 20th century. In this context, further investigation about the authenticity of the Dresden collection was necessary. In 2016 the colourants of all pebbles were investigated by non-destructive methods. According to the data provided by different methods (XRD, Raman-spectroscopy, VIS-spectroscopy) hematite was confirmed to be the basic component of the colourant. Measurement of the colour values by VIS-spectroscopy reveals a scatter only in the red spectrum, indicating that a pure and intense red colour was the intention. Moreover disperse pigments on the surface are measured and either derive from pigments emitted on this site during processing or derive from postsedimentary processes as coloured sediment layers are reported from this site.

Keywords: Mas-d’Azil, colour analysis, X-ray diffractometry (XRD), Raman-spectroscopy, VIS-spectroscopy