Effects and efficiency of consolidation treatments on Palaeolithic reindeer antler. Multi-analytical study by means of XRD, FT-IR microspectroscopy, SEM, TEM and μ-PIXE/PIGE analyses

Bone materials record information on palaeodiets and palaeoenvironment, contained in their chemical and isotopic composition. Therefore, it is very important, while preserving these objects, to keep an open access to this information. In the present paper, we characterise the effects of consolidation treatments on the structure and chemical composition of archaeological reindeer antler at different hierarchical scales. X-ray diffraction, infra-red spectroscopy and microscopy, scanning and transmission electron microscopy coupled with an X-ray analysing system and proton-induced X-ray and γ-ray emission were used to reveal the state of preservation of reindeer antler and to evaluate the effectiveness of their consolidation treatments. These treatments are shown not to affect the chemical composition, but the crystallinity of the solid phase, as far as Palaeolithic material is concerned. In terms of penetration, the most efficient treatment, among those tested, seems to be the Rhodopas 15% single-bath treatment.