“Amarna blue” painted on ancient Egyptian pottery

“Amarna blue” pigments (18 Dynasty, c. 1400 BC) painted on pottery fragments were investigated using the PIXE, XRF and XRD methods in laboratories and also using a portable type of X-ray spectrometer at the sites of excavation. On the blue-colored part enrichment of Na, Al, S, Cl, Ca, Mn, Co, Ni and Zn was found using X-ray spectroscopy, and CaSO4, NaCl and Co(M)Al2O4, M denoting Mn, Fe, Ni and Zn, were found by the help of X-ray diffraction. This means that Amarna blue is a mixture of CaSO4 and Co(M)Al2O4, at least in part.