Spectroscopic study of the coloring techniques used in Egyptian ceramics from the ptolemaic and roman period

The manufacture of the Egyptian Faience through the periods of Ptolemaic and roman shows intense use of polychrome; our main concerns in this research are investigating the parameters controlling the blue color variation and the production of the apple green Faience. Archaeological faience samples belonging to the Ptolemaic and Roman periods representing various color hues were extensively studied using multiple spectroscopic techniques to explore the color palette of the Egyptian artist in this period and highlight the most significant features of their ways of coloring and fabrications. X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) results revealed quartz-rich body feature for all samples, with defined boundaries in some samples due to coloring techniques. The investigated Faience are not lead-alkaline glazes but possibly soda (plant ash) or mixed-alkali glazes with inter-particle glass phases. The high lead content accompanied by antimonite and percentage of sulphur suggested the usage of natron salt flux. The apple green glazes are a yellow lead antimonite mixed with copper oxides. The color varies from deep apple green to light apple green based on the content of oxides in the sample.