FIELD AND LABORATORY MULTI-TECHNIQUE ANALYSIS OF PIGMENTS AND ORGANIC PAINTING MEDIA FROM AN EGYPTIAN COFFIN (XXVI DYNASTY)

This paper describes the physico-chemical analyses performed on an Egyptian wood coffin on the occasion of its restoration in the hall of the National Archaeological Museum of Parma (Italy), with the aim of investigating the pigments and organic materials originally used. Pigment determination was performed both in situ by a portable energy-dispersive X-ray fluorescence (EDXRF) spectrometer and in the laboratory using a micro-Fourier-transforminfrared (micro-FTIR) and a Fourier-transform (FT) Raman spectrometer. The identification of organic materials was performed through gas chromatography – mass spectrometry (GC– MS) and micro-FTIR analysis. Amongst the pigments, special attention was paid to the green, which appeared to be severely degraded and was examined using powder X-ray diffraction (XRD) and scanning electron microscopy – energy-dispersive X-ray (SEM–EDX) in addition to the above-cited techniques. Other materials used in the polychromatic decorations are Egyptian blue, cinnabar and possibly orpiment, while calcium carbonate was used for the ground layer. The organic materials were identified as beeswax, mastic and gum arabic, sometimes as mixtures.