Through X-ray microscopy researchers managed to identify copper as used in ink for writing on 2000-year-old Egyptian papyri.
So far it was believed that ancient Egyptians used mainly carbon-based ink for writing, but a team of researchers identified copper within carbon inks used over a period of 300 years in different geographical regions. The fragments of the papyri, belonging to the Papyrus Carlsberg Collection at the University of Copenhagen, were studied with with advanced synchrotron radiation based X-ray microscopy equipment at the European Synchrotron Radiation Facility in Grenoble. According to Thomas Christiansen from the University of Copenhagen, the composition of the copper-containing carbon inks showed no significant differences that could be related to time periods or geographical locations, which suggests that the ancient Egyptians used the same technology for ink production throughout Egypt from roughly 200 BC to 100 AD. The papyri in the collection came from two sources – from the private papers of an Egyptian soldier named Horus, who was stationed at a military camp in Pathyris, and from the Tebtunis temple library, which is the only surviving large-scale institutional library from ancient Egypt. This discovery might affect future decisions on conservation and safe storage of such artefacts.
(after Thomas Christiansen, University of Copenhagen & EurekAlert!)