New insight on ancient cosmetic preparation by synchrotron-based infrared microscopy

Synchrotron IR micro-spectroscopy is appropriately suited to the analysis of small particles of archaeological cosmetics. The sample originates from a 33 centuries old Egyptian cosmetic remain. Thanks to the high spectral quality and high lateral resolution achieved by this synchrotron-based microspectroscopic tool, new insights into the composition and spatial location of both organic and mineral components of the sample were obtained. Five different particles were analyzed and delivered similar findings: the core is fat rich, and surrounded with a mineral phase. In two particles, lead palmitate was clearly identified as a major component. Phosgenite (Pb2CO3Cl2), a lead salt synthesized in aqueous solution, was also located in region near the surface of the particles.