To test whether ancient scrolls charred by Mount Vesuvius could be read without unrolling, a research team led by Douglas Seiler of UC Berkeley built their own. They obtained Egyptian papyrus and traditional lampblack ink, added trace amounts of lead, and paid high school students to write passages from various texts. After rolling and burning the papyrus to mimic the 79 C.E. eruption that carbonized the Herculaneum library, they scanned the results with X-ray tomography.
The experiment, published in PLOS ONE, confirmed that even extremely small quantities of lead produce a striking contrast in the scans. Lead absorbed roughly 25 times more X-rays than the surrounding burned papyrus, making the written characters clearly visible. The team also showed that a relatively inexpensive handheld X-ray fluorescence scanner can detect lead-based ink in a burned scroll, offering a fast way to identify which scrolls merit full CT imaging.
The technique matters because the Herculaneum scrolls are the only intact library to survive from antiquity, and many works remain trapped inside fragile, carbonized rolls. Earlier attempts to physically unroll them often destroyed the papyrus. While researchers have not yet systematically screened the collection for lead, one previous study detected lead in a fragment from early unwrapping attempts. The new results suggest that searching for lead could dramatically speed up the effort to read these ancient texts without damaging them.