Analytical approach to the conservation of the ancient Egyptian manuscript'Bakai Book of the Dead': a case study

摘要

This work was devoted to identification of ink used in the Egyptian papyrus"Bakai Book of the Dead".The elemental composition of micro-samples was obtained by using Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy.Various areas of the papyrus covered by hieroglyphs were investigated,with the special attention focused on the"white"and"black"ink.Surprisingly,Pb was identified as the main element of the both ink traces.Therefore,the hypothesis was made that galena(PbS)was the main component of the ink used for writing this unique document and that the white colour of the ink is a consequence of the discoloration.In order to verify this assumption and to follow the chemical processes causing this phenomena for the black hieroglyphs model samples were prepared.A mixture of powdered galena and gum Arabic was deposited on Whatman paper support.These models were used at first to evaluate a behaviour of PbS ink in oxidative environment,then to evaluate the possible conservation procedure for the endangered document.