An international team of scientists from the Rijksmuseum, the CNRS, the ESRF the European Synchrotron, the University associated with Amsterdam and the University of Antwerp, have discovered a rare lead compound (named lead formate) in Rembrandt’s masterpiece The night time Watch . This discovery, which is a first within the history of the scientific study of paintings, provides new insight into 17th-century painting technique and the conservation history associated with the artwork. The study is published in Angewandte Chemie — International edition .
The Night Watch , painted in 1642 and today displayed in the Rijksmuseum Amsterdam (The Netherlands), is one of Rembrandt’s most important masterpieces and largest work of art. In the framework of the particular 2019 Operation Night View , the largest research and preservation project ever undertaken for Rembrandt’s work of art, an worldwide research team joined forces to study how the painting materials react chemically and with time.
The team of scientists combined multi-scale imaging methods in order to chemically study the materials used by Rembrandt within The night time Watch . A X-ray scanning instrument developed at the University of Antwerp (Belgium) was applied directly to the particular painting, while tiny fragments taken through the painting were studied with synchrotron micro X-ray probes, at the ESRF, the Western Synchrotron (France), and PETRA-III facility (Germany). These two types of analyses revealed the presence associated with an unexpected organo-metallic compound: guide formates. This particular compound had never been detected before in historic paintings: “In paintings, business lead formates have only already been reported once in 2020, but in model paintings (mock-up, fresh paints). And there, surprise: not only do we discover lead formates, but we identify them in areas where there is no lead pigment, white, yellow. We think that probably they disappear fast, this is why they were not really detected in old master paintings until now, ” explains Victor Gonzalez, CNRS researcher in the Supramolecular plus Macromolecular Photophysics and Photochemistry (PPSM) laboratory (CNRS/ENS Paris-Saclay) and first author of the paper.
Why did this one not vanish then? For Katrien Keune, head of science in Rijksmuseum and professor on the University associated with Amsterdam (the Netherlands), this finding is key to understanding Rembrandt better: “In Procedure Night View we focus on Rembrandt’s artwork technique, the condition of the painting and exactly how we can best preserve it for future generations. The particular lead formate gives us valuable brand new clues about the possible use of lead-based oil paint simply by Rembrandt plus the potential impact associated with oil-based varnishes from past conservation treatments, and the particular complex chemistry of historical oil works of art. inch
What is the origin of this substance? Can this provide information on Rembrandt’s workshop recipes, or shed light on the chemical mechanisms active in the particular layers associated with old paint? To answer these questions, the scientists studied pieces taken from The Night Watch and design samples prepared in the laboratory simulating the painter’s formulations.
They worked with the particular hypothesis that Rembrandt used an organic medium (linseed oil) containing dissolved lead oxide (PbO litharge) to enhance its siccative properties. “Thanks to the unique analytical performance of the ESRF, the particular world’s brightest synchrotron light source, we could map the presence of formates at a micrometric scale, and follow their formation over time, ” explains Marine Cotte, scientist from the ESRF. The spatial organization from the compounds at the micro-scale as well as the dynamics of their formulation made it possible with regard to the researchers to suggest new hypotheses on the chemical substance conditions of their within situ crystallisation in old paint layers.
“In addition to providing information on Rembrandt’s pictorial techniques, this particular research opens up new avenues on the reactivity associated with historical pigments, and therefore upon the preservation of heritage, ” describes Koen Janssens, Professor in the University of Antwerp.
The next step for the particular team is to further study the origin of these formates and see if they could also originate from previous restoration remedies.
Note: This study benefits from the facilitated access provided in order to the historical materials community to the synchrotron techniques on the ESRF, that has been implemented with support from the particular European Union’s Horizon 2020 research plus innovation programme under grant agreement No 870313, Streamline.