A discipline born in the wake of archaeology, archaeometry makes it possible today to reveal new information on the techniques used by an artist in carrying out his or her work. The interfaculty research unit AAP and the European Centre of Archaeology - hosted by the University of Liège - position themselves more than ever as the actors of a scientific approach applied to works through the development of several innovative, mobile, and non-invasive techniques.
rchaeometry may be defined as the encounter of the humanities with exact and natural sciences. Whereas archaeology allows us to gather information related to the provenance, organisation, or evolution of a society, archaeometry, on the other hand, combines techniques developed in laboratories in order to provide information enabling us to evaluate the compositions, developments in manufacturing techniques and material wear of archaeological objects and works of art, in particular.
Archaeometry is developed around 3 main axes of research: archaeology, art history, and heritage conservation. This scientific branch includes much knowledge and expertise, which come from several scientific disciplines. "Today, we talk more about Technical Arts History, stresses David Strivay, director of the interfaculty research unit AAP (Art, Archaeology, Patrimony) and the European Centre for Archaeometry. In addition to the analysis of the artistic significance of the works, we are now trying to recover the manner in which the artists worked, to reveal their gestures, the way in which they carried out the work, the composition of the materials that they used, which allows us to follow the evolution of the techniques used by the artists throughout their careers, their changes in practice and their reworkings. This also allows us to explain the occurrence of damages to the work in order to pursue techniques for their restoration." This work is possible thanks to the implementation of new tools and new innovative analysis and imaging techniques.
Developing mobile tools
"Before, we had to physically move the works to analyse them in our laboratories, explains David Strivay, which could prove to be quite expensive in certain cases, or downright impossible in the case of murals." At that time, we had no choice but to use sampling, which was very damaging to the analysed works. Today we're doing the opposite: it's the researchers who are going to the work." The development of new mobile tools now makes it possible for researchers to analyse the works in situ, in a cave, a museum, or in a private home. Indeed, the burden of the processes used before is leaning towards a more lightened approach. It is now giving way to portable analysis tools developed at the European Centre for Archaeometry, which are can fit in a suitcase by a researcher in order to perform analyses. This makes it possible to reduce the manipulation of works and, above all, in the case of archaeological sites, to go to the most remote locations.
Developing innovative and non-invasive techniques
The developed analysis techniques are also making it possible to no longer "touch" the work. "Whereas before we analysed the work under purely physicochemical aspects, today we are developing techniques tied to imaging, which enable us to "see" the work from every angle,” continues David Strivay. “An image is more meaningful and more complete than a single point of analysis, as we were able to estimate before from a sampling." All imaging techniques are used: classic high-resolution imaging for the visible, ultraviolet, and infrared, but also x-rays, fluorescence imaging, Raman and FTIR spectroscopy, gas analysers, colorimetry, etc. Only particle accelerators are still in the labs today. These techniques have allowed for the discovery of several reworkings (masking or highlighting characters, objects, or bodies and their position) and other alterations made by artists to their work at the moment of their creation, and which remain invisible to the naked eye.
University of Liège researchers are working on the development of even more innovative techniques which may eventually allow for the analysis of works in three dimensions through the use of more powerful and lighter tools, which could be obtained from a mobile phone.
Conserving and restoring
Because the works age and undergo the horrors of time and conservation conditions in which they find themselves, the University of Liège scientists offer techniques aimed at the conservation and restoration of works of art. "We try to identify the problems which have arisen or will arise,” explains David Strivay. “More and more, restorers and art galleries are relying on us to identify the problems and to try and resolve them by proposing solutions regarding conservation or the use of new materials to restore them. Our techniques make it possible to seek out the origin of certain alterations to better face them." The scientists also have access to modelling in order to consider the effects that the conservation conditions could have on a work concerning its evolution, and to develop the appropriate restoration techniques to be used.
The work of scientists is just not confined, however, to works from the past, but is also turned toward contemporary art. "The artist is not always aware of what he or she is using, and of the incompatibility of certain materials with others. In these cases, we try to bring forth solutions so that the works maintain their lustre by performing a study on the material and its properties."
With its experience and the recognition of its expertise, the University of Liège Centre collaborates with several public and private organisations, and offers its services in assisting in the authentication of works of art. "We do not authenticate a work of art per se, but we aid the restorers and the experts in identifying the errors made by potential counterfeiters through the analysis of artistic techniques, pigments or basic materials used through several tools and techniques that we offer", concludes David Strivay.
One thing is certain: the use of new techniques developed by the scientists and historians from the University of Liège now seems to be prevailing in such areas as Art History and Archaeology.
The European Centre of Archaeometry: A Centre for Study and Teaching
Founded in 2003, the European Centre of Archaeometry has specialised in the study of movable and immovable cultural heritage. The research themes address the question of materials and their implementation by comparing historical and archaeological data with the results of scientific analyses. Housed within the University of Liège, the Centre works in close collaboration with art historians, archaeologists, and scientists from the Faculty of Science.
The European Centre of Archaeometry collaborates with several public Belgian bodies (IRPA, the University of Antwerp and Ghent, Royal Museums of Art and History, Museums of the City of Liège), as well as entities abroad (C2RMF, LAMS - University Pierre and Marie Curie, Getty Conservation Institute, etc.).
The Centre also organises a Masters in Archaeometry, the only one of its kind in French-speaking Belgium.
Magritte, a mystery finally solved
The fourth and last part of Magritte's art work "The Enchanted Pose" discovered by ULiège researchers under the painting "God is not a Saint" at the Magritte Museum!