A blue paint layer sample was collected from the wall decorations of the mortuary temple of Ramesses III (Medinet Habu. This temple is one of the largest memorial temples in Egypt. It measures 320 m in length (east to west) and about 200 m in width (north to south), built with order of the Pharaoh Ramesses III (c.1184–1151 BC the 20th Dynasty). The micro-XRF spectrometer (SPECTRO, COPRA model) used to analyze the sample includes a side-window X-ray tube with Mo anode (Oxford Instruments, Series 5011 XTF), potential acceleration 35 kV, lamp stream 0.9mA and with analysis time 300 s. A long-distance optical microscope located on the detector and X-ray tube plane is used in order to select the points of interest over the surface of …show more content…
El-Bagawat is located about 3km from the centre of El-Kharga Oasis in the western desert of Egypt. El-Bagawat is perhaps the oldest major Christian cemetery in the world; it is dating back to the 4th century AD, which were built over the site of an earlier Egyptian necropolis of pit graves. The architectural style of the 263 tomb-chapels varies from simple one-room structures to family mausoleums with ornate façades enhanced with faux columns and arches and domed roofs. Although many of the chapels were undecorated and consisted simply of a single chamber built over the tomb shaft, some were much more elaborate and contained plastered walls with painted biblical scenes in a strange mixture of styles while others have elements reminiscent of earlier Egyptian architecture. Two of the most outstanding and best preserved of the decorated chapels are named ‘Chapel of the Exodus’ and ‘Chapel of Peace’. Raman spectra were recorded using a Renishaw InVia Raman spectrometer in the near infra red excitation line (785 nm) of a diode laser source. The instrument is equipped with Peltier cooled charge coupled device (CCD 576x400 pixels). A Leica DMLM microscope with a XYZ motorized stage with 200 and 500 magnification objectives is equipped to Raman spectrometer which can provide a sample irradiation diameter of up to 1 μm. A polarized unit system is mounted onto the microscope which offers a clear view of the area under investigation, necessary for positioning the beam on individual pigment particles. The lower laser powers (up to 0.5 mW) were used to avoid inducing thermal changes to the mineralogy of the iron oxide minerals. Typical exposure time of the CCD was 20s per scan, while normally 5 up to 20 accumulations were co-added to produce the final spectrum in order to improve the signal-to-noise ratios. The microscopic unit attached to Raman instrument was helpful in recording spectra on