Are they the work of Caravaggio? That is the question the world's leading art experts are asking themselves over 100 previously ignored paintings and sketches discovered in a Milanese castle.
The pieces, which have been valued at $861m, were previously attributed to his teacher, Simone Peterzano, under whom the future Renaissance master studied between 1584 and 1588.
Maurizio Bernardelli Curuz, a co-author of the book that puts forward the case for the artworks, told Sky News: "Evidently no one entertained the hypothesis that there were works of his pupils, including future star artist Caravaggio, among the drawings."
Caravaggio, who spent several years running from the authorities after mortally stabbing an opponent during a tennis match in 1606, is rarely seen at auction. Among the most important of his privately owned works is the 1600 Conversion of St Paul, valued at around $150m, according to theartwolf.com website.
Unlikely as it may be, were any of these newly attributed works to appear for sale in the future we could expect to see sky-high results.
That's because the excitement that surrounds discovered works often pushes such pieces well beyond their intrinsic value (see Paul Fraser Collectibles' guide to the top 5 long lost artworks here).
We've seen it happen with Nu adosse I, by Polish artist Tamara de Lempicka, which sold for $5.4m earlier this year.
The 1925 piece, previously thought lost, beat its $5m high estimate by 9.17% at Sotheby's in May.
A similar excitement builds around artworks that, although not lost, have remained away from public view for a long period of time. William Adolphe Bouguereau's Idylle: famille antique, last seen in public 50 years ago, and which beat its estimate by 30.4% with a $782,500 showing, is a case in point.
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