Tracking ink composition on Herculaneum papyrus scrolls: quantification and speciation of lead by X-ray based techniques and Monte Carlo simulations

Pieter Tack (1) , Marine Cotte (2, 3) , Stephen Bauters (1, 2) , Emmanuel Brun (4) , Dipanjan Banerjee (2) , Wim Bras (2) , Claudio Ferrero (2) , Daniel Delattre (5) , Vito Mocella (6) , Laszlo Vincze (1)

1 UGENT - Universiteit Gent = Ghent University
2 ESRF - European Synchrotron Radiation Facility
3 LAMS - Laboratoire d'Archéologie Moléculaire et Structurale
4 GIN - [GIN] Grenoble Institut des Neurosciences
5 IRHT - Institut de recherche et d'histoire des textes
6 IMM - Istituto per la Microelettronica e Microsistemi [Catania]

The writing in carbonized Herculaneum scrolls, covered and preserved by the pyroclastic events of the Vesuvius in 79 AD, was recently revealed using X-ray phase-contrast tomography, without the need of unrolling the sensitive scrolls. Unfortunately, some of the text is difficult to read due to the interference of the papyrus fibers crossing the written text vertically and horizontally. Recently, lead was found as an elemental constituent in the writing, rendering the text more clearly readable when monitoring the lead X-ray fluorescence signal. Here, several hypotheses are postulated for the origin and state of lead in the papyrus writing. Multi-scale X-ray fluorescence micro-imaging, Monte Carlo quantification and X-ray absorption microspectroscopy experiments are used to provide additional information on the ink composition, in an attempt to determine the origin of the lead in the Herculaneum scrolls and validate the postulated hypotheses.

Domaines: Chimie

Pieter Tack, Marine Cotte, Stephen Bauters, Emmanuel Brun, Dipanjan Banerjee, et al.. Tracking ink composition on Herculaneum papyrus scrolls: quantification and speciation of lead by X-ray based techniques and Monte Carlo simulations. Scientific Reports, 2016, 6, pp.20763. ⟨10.1038/srep20763⟩. ⟨hal-01279464⟩