In the last two decades, the Bundesanstalt für Materialforschug und -prüfung (BAM), together with the Centre for the Study of Manuscript Cultures (CSMC, University of Hamburg), has analysed manuscript materials, with a special emphasis on inks, in order to reconstruct their history and development. Black inks are typically divided into three types: carbon inks, made of carbon pigments dispersed in water with a binding agent; plant or tannin inks with soluble extracts from tree bark or gallnuts; and iron-gall inks, produced by a chemical reaction of divalent iron (Fe++) with gallic or tannic acid in a water-soluble binding media. Roughly speaking, carbon inks appeared fi rst and prevailed during the whole period of Antiquity; they were gradually replaced by iron-gall inks, which dominated the palette of black writing inks in the Middle Ages in Europe and the Islamicate world. In recent years, we have focussed our attention on the transition period that lasted for more than a thousand years and involved various metals and mixed inks.1 In a recently published detailed study of the oldest known metal-containing ink, Nehring and co-authors stressed the distinct appearance of a tannin- containing ink on papyrus, which diffuses beyond the letters, smearing the edges and producing a brownish “halo”. In this context, inks from P. Berol. inv. 5026 appear particularly interesting to investigate, because black inks with sharply defi ned contours alternate with the brownish and blurry ones. This paper investigates the composition of the inks from P. Berol. inv. 5026 and the possible reasons for the use of the different inks.

The research for this article was partially funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC 2176 'Understanding Written Artefacts: Material, Interaction and Transmission in Manuscript Cultures', project no. 390893796. The research was conducted within the scope of the Centre for the Study of Manuscript Cultures (CSMC) at Universität Hamburg.