In fact, Grosvenor says we’re “potentially in a golden age for finding pictures” in public collections that have long been overlooked. Several
paintings have turned up just this year. In July, two frescoes in the Vatican thought to be the work of ’s
students were determined be by the master himself. In October, a New Jersey town announced that a bust of Napoleon Bonaparte, on display for over 80 years in the council chambers of a local borough hall, was actually a long-lost work by
“In all these examples, somebody took a little extra time or by accident looked at something more closely, maybe because they were just passing by or because they were working on a specific project,” said Petria Noble, head of paintings conservation of Amsterdam’s Rijksmuseum
, who specializes in restoring 17th-century Dutch masterpieces.
Noble said there is one category of Old Master painting that is now being “discovered” more often than others: oil sketches, or full-scale oil paintings that are either unfinished preparations for a larger work or finished works that appear unfinished because of their loose brushwork.
The Rubens in Glasgow is one such work. It was likely an oil sketch that was later “completed” by another artist who thought he was improving it. As a result, the master’s original artistry was long hidden. A number of recently rediscovered paintings by
also fall into this category, Noble noted.
“For a long time art historians didn’t know what to think of these kinds of works,” she said. “But now, because of new historical and technical research, these things are being rediscovered and put into their proper context. It’s a complex area, and sometimes it takes time for a consensus to be developed among experts, but as technology evolves and there’s more consensus there will be new pictures discovered.”
Macro X-ray fluorescence, for example, is a new, non-invasive tool that allows specialists to scan the surface of a painting and collect data on pigments without ever touching the artwork. Advances in dendrochronological research, the dating of wood panels, have also allowed researchers to more precisely determine the year a work of art was made—often a crucial data point.
“These tools can contribute to a much more refined kind of connoisseurship that is not wholly dependent on an expert’s eye—and I still believe in the expert eye, that always has to be the point of departure,” said Anna Tummers, a curator at the Frans Hals Museum in Haarlem and author of the book, The Eye of the Connoisseur: Authenticating Paintings by Rembrandt and His Contemporaries. “If you can also look below the surface and take the materials into account, that gives you a more refined picture.”