A new study published in the peer reviewed journal Surface Topography: Metrology and Properties introduces a pioneering, non‑invasive technique that can distinguish authentic artworks from forgeries, offering museums, collectors and auction houses a major advantage in tackling art fraud.
The study, developed at the Université Polytechnique Hauts-de-France introduces a method that analyses the microscopic "texture" of a painting by converting high-resolution images into 3D‑like maps allowing researchers to measure how rough or detailed the surface is using fractal dimensions. This measurement captures subtle patterns created by an artist's brushwork – patterns so consistent that they act like a morphological signature unique to that artist.
Using works attributed to Vincent van Gogh, the researchers showed that the method can reliably distinguish between authentic paintings and known forgeries. In tests, the well‑documented fake The Plowmen was identified as a strong outlier, while the recently authenticated Sunset at Montmajour aligned closely with Van Gogh's known works. The approach also successfully separated the stylistic signatures of Van Gogh and 17th‑century painter David Klöcker Ehrenstrahl, demonstrating its wider potential.
Art forgery is a growing problem, and traditional authentication relies on a combination of expert opinion, historical research, pigment analysis and digital techniques. These approaches are powerful but also resource‑intensive and sometimes inconclusive. This technology can strengthen authentication, especially when combined with complementary analyses such as the chemical examination of materials, while reducing financial risk and helping to safeguard cultural heritage
The urgency for better authentication tools has never been clearer. A recent investigation reported by The Guardian revealed that AI technology identified up to 40 counterfeit artworks, including pieces labelled as Monet and Renoir, being sold on major online marketplaces. In these cases, scientists provide analysis that helps experts make informed decisions. Using a range of different methods leads to more reliable conclusions, helping to detect fraud and protect cultural heritage.
Lead researcher of the study, Francois Berkmans, says: "Fractal analysis gives us a measurable fingerprint of an artist's brushwork without needing to sample or disturb the painting. This approach won't replace traditional expertise, but it significantly strengthens it. Our results show that our technique can clearly point out genuine artists and reliable detect known forgeries."
