Master paintings, medieval silverware, entire violins and gold bracelets worth millions of dollars – is no museum piece exempt from the intense X-ray scrutiny of synchrotrons to help scholars understand and preserve our cultural heritage? These and many more precious objects were the subject of the 2012 Synchrotron Radiation in Art and Archaeology (SR2A) symposium held at the Metropolitan Museum of Art, New York, between 6–8 June – the fifth such meeting since its inauguration in Grenoble in 2005 by the ESRF and CNRS.
Synchrotrons are clearly making a big impression on the museum scene. Techniques such as X-ray fluorescence and X-ray absorption near edge structure (XANES) can reveal why certain paint pigments become discoloured, and at the ESRF’s ID21 beamline are providing insights in how to preserve vibrant works by artists such as Van Gogh and Matisse. The manufacturing methods employed in early ceramics and glass were another main topic of discussion at the New York event – a three-day feast of histograms and beautiful visuals spanning thousands of years of human history.
We were treated, occasionally accompanied by the sounds of excited school children visiting nearby galleries, to stunning tomographic images of sub-mm workmanship in a 260-year-old violin; diffraction experiments that can authenticate ancient astronomical computers; chemical maps from tree rings that may help pinpoint volcanic eruptions; and XANES spectra of fossilised feathers that reveal the colourful new world of paleobiology. Maisoon Al-Jawad from Queen Mary University in the UK described how she is using the ESRF to develop models of archaeological enamel that could lead to bioactive dental repairs.
It was also clear that there remain barriers between the art and science worlds. “The use of synchrotron-based X-ray techniques remains marginal, mostly because cultural-heritage specialists rarely interact with synchrotron specialists,” said physicist Volker Rose of the Argonne National Laboratory, who presented new opportunities arising in nanoscale cultural heritage research. Ironically, Rose summed up the situation using analogies that only a physicist could love: the tendency of a system to minimise its potential energy and the notion of overlapping quantum wavefunctions.
The “extreme heterogeneity” of historic materials is one reason why the cultural heritage community is yet to take full advantage of synchrotrons, argues chemist Matija Strlic of University College London. “Scientific characterisation of material behaviour is carried out on a variety of scales, but not all measurable change on the micro scale is necessarily viewed as damage by curators or the public,” he stated.
Getting straight to the point, conservator David Thurrowgod of the National Gallery of Victoria, who has used the Australian Synchrotron to reveal lost paintings behind works by Degas and Streeton, said that curators want to know whether it’s safe to put a $50 m painting in a beam, or if it’s going to burn a hole, adding that he has tried but been unable to detect any damage in paintings that have been irradiated in synchrotrons. Franco Zanini of Italy’s Elettra also faced difficulties in convincing the owners of classic violins (which can be worth upwards of €20 m) to put their instruments on his beamline. “Now that we have shown that it is safe, more people are interested in using the technique,” said Zanini.
Art historians who spoke to ESRFnews – two of whom, interestingly, made their primary living from jobs as hospital radiographers – see no conflict, at least in principle, between the two cultures. They are enthusiastic about the use of synchrotrons, especially for helping to determine the provenance and authenticity of paintings and artefacts.
But connoisseurship will always play a central role according to the Met’s curator for European paintings Walter Liedtke, who likens the situation to identifying a good wine. “If you want to know that a particular red wine is from the north of Italy, a chemist can tell you that,” he told ESRFnews from his bookshelf-flanked office tucked behind locked doors in the Met’s Rubens and Rembrandt galleries. “But if you want to know that it’s a 1982 Barolo worth 300 bucks a bottle, then you need to talk to someone who has had a lot of it.” Liedtke added that he would be keen for synchrotrons to help him decipher text that appears to be hidden beneath a painting in his gallery by Flemmish artist Anthony van Dyck.
Connecting with curators is key to carrying out new and relevant cultural heritage research, and half of the attendees at this year’s SR2A event said that they had made new contacts for research projects in this high-profile and rapidly growing field of synchrotron science. “Attendees have unanimously remarked upon the very significant progress in the field over the past years,” concluded Loïc Bertrand, director of the IPANEMA European ancient materials research platform at Synchrotron Soleil. “We therefore think that more public and private support could be brought to consolidate existing interface projects and infrastructures, and to foster the creation of novel tools using synchrotron radiation.”
The event was co-organised by the Metropolitan Museum of Art of New York, the Conservation Center at the Institute of Fine Arts of New York University, the Winterthur Museum, Cornell University and Brookhaven National Laboratory.
This article appeared in ESRFnews, July 2012.
To register for a free subscription and to rapidly receive the current issue, please go to: ESRFNews Digital Edition Subscription.