Vincent van Gogh painting that was dumped in an attic has been found and confirmed by experts as authentic.
The painting, "Sunset at Montmajour", is the first full-size van Gogh to emerge for 85 years after it had been banished to a Norwegian attic for more than a century when its owner believed it was a fake.
According to letters from the Dutch master to his brother Theo, the painting was done in 1888 when van Gogh was living in Arles, southern France. However, the notoriously self-critical artist wrote that he did not like the painting and that it was "well below what I'd wished to do". As such, he did not put his signature on it.
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The painting was listed in his brother's personal collection before he sold it to a Norwegian industrialist called Christian Mustad in 1908. It is believed that Mustad was told it was a forgery or false attribution and so he put it in the attic. On his death in 1970, it was sold on to a private collector.
When the collector first asked the Van Gogh museum in Amsterdam for an opinion on the painting in 1991, researchers concluded it was a fake because of the lack of signature. Thanks to modern technology, however, researchers could correlate the literary evidence and artist's style and technique with an analysis of the materials used to prove it was authentic.
"Stylistically and technically there are numerous parallels with other Van Gogh paintings from the summer of 1888," senior researchers Louis van Tilborgh and Teio Meedendorp said of the discovery on Monday when it was unveiled at the museum.
The painting will now go on display in the artist's eponymous museum for a year. If it was to go on sale, it could fetch millions as other works by Van Gogh have done, such as the famous "Sunflowers" piece which sold for $39.9 million in 1987.
- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt