Author(s):
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Dooryhée, Eric |
URL:
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http://srs.dl.ac.uk/arch/ssrl/dooryhee/stanford_talk/ |
Format:
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Presentation |
Source:
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Applications of Synchrotron Techniques in Art and Archaeology Workshop 27th Annual SSRL Users Meeting, Stanford, CA. - October 18th, 2000 |
"Green, white and black make-up has been used since the earliest periods of Egyptian history for their aesthetic and therapeutic properties. We have examined both the inorganic and organic contents of cosmetics dated between 2000 and 1200 BC, kept in an exceptionally good state in their original containers and preserved in the Louvre Museum. Two well-known natural lead-based compounds are identified: the crushed ore of galena (PbS) and the cerussite (PbCO3)- In addition, our analyses reveal the presence of two unexpected synthetic products: laurionite (PbOHCl) and phosgenite (Pb2Cl2CO3). The respective mass fractions of the ingredients are determined by the means of synchrotron X-ray powder diffraction. The proportions are compared with recipes inscribed on some receptacles and on the medical papyri. In addition, the observations by Scanning Electron Microscopy and the analysis of the X-ray diffraction line profiles give some insight into the microstructure of the main minerals, and provide some evidence on the methods of preparation (chemical synthesis, crushing, sieving). Using micro-diffraction and micro-fluorescence, we also identify and estimate the relative abundance of the trace elements present (Fe, Ni, Cu, Zn, Ag, Sb), in relation with their extraction provenance. Combining powder diffraction and micro-beam measurements, we emphasise the capability of synchrotron techniques to describe minerals of great archaeological interest. These detailed investigations into such materials provide further information on some practices and ways of living in the Antiquity."
Permalink: |
http://etana.org/node/8914 |