Rock Art Research

This paper presents the results of experiments testing the long-suggested possibility that colour gradations in the repatination of petroglyphs might be quantifiable for purposes of age estimation. Colorimetric readings from a series of engraved and repatinated dates found among major petroglyph concentrations in the Pilbara of Western Australia and from petroglyphs at Jabal Qara in southern Saudi Arabia are reported. They show fairly good consistency when plotted by age, raising the possibility of using this method for dating petroglyphs under favourable conditions. The method also has significant applications in rock art conservation and condition monitoring work.