X-rays read how palm-leaf manuscripts were made, without cutting a sample

Scientists in Germany have used powerful synchrotron X-rays and machine learning to read the physical history of palm-leaf manuscripts from South and Southeast Asia without cutting a single sample from them, according to a study published in the journal npj Heritage Science and announced by the University of Hamburg's Centre for the Study of Manuscript Cultures (CSMC) on October 15, 2026. The team, led by Laura Gallardo, examined 160 material entries, 85 of them manuscripts and 75 modern reference materials, at the P62 experimental station of the PETRA III X-ray source at DESY in Hamburg and at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. They found that the two palm genera used for writing could be told apart from their material traits, and that the way leaves were processed left a measurable signature. The origin of a manuscript was harder to pin down: samples from Sri Lanka and southern India looked alike, while Thai samples stood apart.

Prepared palm leaves carried a large share of the written texts of South and Southeast Asia, and the problem the study addresses is that a manuscript often does not say where or how it was made. Knowing which palm a leaf came from and how it was prepared can help scholars place an undated text in a region or a workshop, and can tell conservators how to care for it.

The difficulty has always been that the leaves are fragile. Older methods of analysis often needed a small piece to be cut away. The Hamburg approach avoids that. According to the researchers, the value of the method is that it gives detailed structural and chemical information without taking any sample, and that combining several techniques lets scientists read several layers of a manuscript's history in one experiment.

The results are a careful first step rather than a final answer. Co-author Patrick Huber cautioned that the material data alone cannot yet establish where a manuscript came from with certainty. The similarity between Sri Lankan and southern Indian leaves is itself telling: it fits the long, shared manuscript culture across the region, but it means that the method cannot yet separate the two.

For Indian readers, the study connects to work at home. India is in the middle of a national effort, the Gyan Bharatam Mission, to survey and digitise its manuscripts, and palm-leaf collections are part of that work. Digitisation preserves what is written; studies like this one aim to recover what the object itself can say about its making, which a scan cannot capture. The Hamburg centre has also run a palm-leaf manuscript profiling project with work in Pondicherry.

Short-term: Conservators and manuscript libraries gain a tested, non-destructive way to identify the palm used and to detect how leaves were treated, which can guide storage and repair.

Long-term: With larger reference collections, the method could help date and place undated manuscripts, adding physical evidence to what scholars learn from script and language.

Who is affected: Manuscript libraries and archives in India, Sri Lanka and Southeast Asia, scholars of Sanskrit, Tamil, Pali and other manuscript traditions, conservation scientists, and digitisation projects.

Questions and Answers