PHOENIX: Revitalizing Heritage Sciences at UNamur

Heritage sciences are experiencing a resurgence at UNamur. This field of research—which involves applying techniques and expertise from the exact sciences (physics, chemistry, biology) to study ancient heritage objects—is reinventing itself thanks to the PHOENIX project, led by seven researchers from the Faculties of Science (Department of Physics) and Philosophy and Letters (Departments of History and Classical Languages and Literatures). 

“PHOENIX emerged from the collaboration of several researchers from different backgrounds, yet all driven by the same desire to study the materiality of heritage objects. One notable figure is Julien Colaux, whose predecessor had led the first heritage science projects at UNamur’s Laboratory of Analysis by Nuclear Reactions (LARN). It’s a sort of return to our roots,” recalls Nicolas Ruffini-Ronzani, a researcher in the Department of History, president of the PaTHs Institute, and one of the project’s leaders. 

With PHOENIX, researchers aim to “make” two types of objects speak: ancient coins and medieval parchments (see box). More specifically, their research is guided by three objectives:

• To understand the composition of the artifacts being studied. For the parchments, to identify the animal species (sheep, goat, or calf); and for the coins, to characterize the metal alloy.
• Gain a better understanding of the production and processing workflow. For example, determine which parts of the animal were used in the production of a parchment.
• To propose the most precise dating possible. 

It is in this last objective that the main challenge lies. “We won’t be able to date these objects to within a year,” warns Olivier Deparis, a professor in the Department of Physics and a member of the NISM research institute. “The idea is to provide a time frame that is as precise, if not more so, than that already provided by paleography (the study of ancient scripts) or textual analysis. If we can narrow it down to a quarter-century, that will already be a significant step forward.”

To achieve this, the PHOENIX team uses various non-invasive techniques, in particular infrared and Raman spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), and ion beam analysis (IBA). These approaches—which utilize UNamur’s state-of-the-art tools such as the ALTAÏS particle accelerator (see Omalius #36)—provide detailed information on the physicochemical composition of materials, such as the animal origin and ink formulations for parchments or the type of metal alloy for coins. “The use of the exact sciences will enrich our studies and thus allow us to better understand how these objects were produced in the past,” explains Nicolas Ruffini-Ronzani. “Contrary to what one might think, collaboration between the humanities and the exact sciences has a long history, dating back to the 19^th century, and even much earlier in the case of coins.”

These tools will make it possible to examine parchments and coins down to the finest detail, at the pixel level. These in-depth analyses therefore generate a colossal volume of raw data to process. This is where artificial intelligence comes into play to speed up the processing and reveal the information “hidden” in the data, identifying major trends invisible to the naked eye. 

Above all, it will provide a boost in meeting the challenge of dating the objects under study. Dated documents, such as charters, will thus be used as references to test the model’s robustness by comparing the results obtained with already known dates. “If the results are convincing, the technique could be applied to undated documents,” says Nicolas Ruffini-Ronzani. This would represent a significant breakthrough in historical research.

“The use of machine learning methods is not a panacea,” Olivier Deparis qualifies, however. “We wanted to explore it as an open-ended question to assess its benefits.”

PHOENIX could thus herald a new era for heritage sciences, where artificial intelligence—much like the phoenix after which the project is named—opens up new ways to analyze and understand materials from the past.

• Francesca Cecchet (Department of Physics – NISM and NARILIS Institutes)
• Lucas Baseil (Department of Physics – NISM Institute)
• Julien Colaux (Department of Physics – NISM and PaTHs Institutes)
• Olivier Deparis (Department of Physics – NISM, naXys, and PaTHs Institutes)
• Christophe Flament (Department of Classical Languages and Literatures – PaTHs Institute)
• Louise Fauchier (Department of Classical Languages and Literature – PaTHs Institute)
• Laurent Houssiau (Department of Physics – NISM Institute)
• Alexandre Mayer (Department of Physics – NISM and naXys Institutes)
• Giulia Morabito (Department of Physics – NISM and PaTHs Institutes)
• Nicolas Ruffini-Ronzani (Department of History – PaTHs Institute)
• Nicolas Gros (Department of Physics – NISM and PaTHs Institutes)
• Manon Bart (Department of Physics – NISM and naXys Institutes)

The PHOENIX project is funded by the Concerted Research Action (ARC) program from September 2024 to August 2029. It is a continuation of the interdisciplinary Pergamenum21 project, launched in 2014 by the Moretus Plantin University Library (BUMP) under the leadership of Professor Olivier Deparis and dedicated to the scientific study of parchment with a view to improving conservation practices.

Young people from Rochefort showcased the PHOENIX project at the international First Lego League competition, a robotics contest open to students aged 10 to 16. To align with the annual theme focused on new technologies in the field of archaeology, this team from the Rochefort Youth and Culture Center drew inspiration from IBA technology to develop a research game designed to identify the origin of Ancient Greek coins modeled using a 3D printer. Their project caught the jury’s eye and earned them a spot in the national finals, which took place last March. Beyond the competition, this original game will be presented during Family Day at the Malagne Archaeological Park (Rochefort).