Can color be used as a proxy for paleoenvironmental reconstructions based on archaeological bones? El Harhoura (Morocco) case study

Abstract : The El Harhoura 2 cave (Temara region, Morocco) has yielded abundant micromammal remains. Eleven sedimentary layers have been identified in the Late Pleistocene-Middle Holocene series. Rodent bones show various colours from white to black. Conodont colour alteration index is a widely used technique for assessing maturation and diagenesis. Despite fossil and archaeological bones may be black due to mineral staining (manganese) or burning, a similar index does not exist. We perform colour measurements in the visible light of the external surface of archaeological Meriones bones. Specific wavelengths were then selected for multivariate statistical analyses to try to characterize and differentiate the sedimentary layers. In this preliminary study, the origin of the colour is not yet known, despite some spots are Mn deposits. In the future, we hope that colour measurement, a non destructive analysis, will be used as a taphonomic index to estimate the state of preservation and history of fossil and archaeological sites.