Scientists who analysed 2,000-year-old papyri fragments have revealed that, black ink used by Egyptian scribes contained copper.
Until recently, it was assumed that the ink used for writing was primarily carbon-based at least until the fourth and fifth centuries AD.
However, analyses of with X-ray microscopy show that black ink used by Egyptian scribes also contained copper – an element previously not identified in ancient ink.
In the study published in the journal Scientific Reports, researchers showed that Egyptians used carbon inks that contained copper, which has not been identified in ancient ink before.
Although the analysed papyri fragments were written over a period of 300 years and from different geographical regions, the results did not vary significantly.
The papyri fragments were investigated with advanced synchrotron radiation based X-ray microscopy equipment, and the particles found in the inks indicate that they were by-products of the extraction of copper from sulphurous ores.
The studied papyri fragments come from two primary sources: 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.
The results will also be useful for conservation purposes as detailed knowledge of the material’s composition could help museums and collections make the right decisions regarding conservation and storage of papyri, thus ensuring their preservation and longevity.