A model carbonized papyrus scroll opens a novel path to identifying readable scrolls of the Herculaneum Library

We report the successful fabrication of a laboratory-made carbonized papyrus scroll and the virtual unrolling and reading of its custom leaded ink text, using X-ray tomography. We believe this is the first confirmed proof of concept to show that the presence of lead in Herculaneum scrolls would greatly increase the probability for successful reading. This synthetic model enables systematic variation of ink formulations, including leaded inks, to generate ground-truth datasets for the development and validation of text-detection algorithms intended for use on the Herculaneum scrolls. By altering the ink composition from pure carbon to an ink enriched with lead, an X-ray contrasting agent, our team can provide datasets which can be used to test algorithmic performance. Inks containing only carbon present a more challenging detection scenario, serving as a baseline for recovery efforts. The lab-made scroll was constructed from modern Egyptian papyrus and ink incorporating a soluble lead salt, then carbonized and imaged using a laboratory-grade X-ray tomography system. The scroll was virtually unrolled using custom-developed software. Additionally, we found that a handheld X-ray fluorescence (XRF) device could detect lead in the ink post-carbonization. This suggests that XRF may be a practical screening method for identifying ancient scrolls likely to contain lead-based ink and therefore have a higher probability of being successfully read.