The Egyptian green pigment: Its manufacturing process and links to Egyptian blue

The chemical and structural analysis of raw Egyptian blue and green pigment cakes and of 50 pigment samples taken from paintings kept in the Louvre Museum was performed using a set of analytical techniques (X-ray powder diffraction, transmission and scanning electron microscopy. Raman microscopy and UV spectrophotometry). The structural and morphological study of modern samples prepared on the basis of these results has provided technological data that help to explain ancient procedures. The role of the firing temperature, the atmospheric conditions in the furnace and the cooling rate are considered. The difference between Egyptian blue and Egyptian green pigment is proved. Manufacturing processes for their deliberate synthesis are proposed.