Study of the degradation of papyrus from Ancient Egypt using XRD-laminography

The objective of this proposal is to gain insight into the degradation processes taking place at the surface of illustrated papyrus from Ancient Egypt. We are investigating a series of illustrated papyrus from Champollion’s private collection, showing scenes from the Book of the Dead. Through X-ray diffraction experiments at ID22, we identified several compounds resulting from a degradation process, especially at the interface between yellow As-based and green Cu-based regions, resulting in the formation of a series of mixed As/Cu compounds. To better understand the reaction pathway leading to the formation of these degradation phases, we intend to perform X-ray diffraction mapping using a laminography approach, a technique well-suited to the 3D mapping of flat samples. In such a way, the 3D organisation of the different painted layers and degradation compounds will be retrieved in a non-invasive way.