Art world divided over Caravaggio 100 works discovery There are documents which attest to the fact that he spent four years in the studio of Peterzano. It's clear that he would have produced some works in those years. But other experts were dismissive of the claims. Dr John T. Spike, a Caravaggio expert at the College of William and Mary in Williamsburg, Virginia, said the quality of the sketches was better than Caravaggio's earliest known work, Boy Peeling Fruit, painted in 1592. "The sketches from the collection show robust, competent drawing, yet in Caravaggio's earliest painting he was struggling to draw competently," he told The Daily Telegraph. How could he have gone backwards in terms of his artistic skill? He said one of the sketches acclaimed as the work of Caravaggio appeared to have been based on a sculpture from 1601 - more than a decade after he was working under Peterzano's tutelage. These sketches could have been by anybody. Young artists studied in groups and used the same artistic language," he said. The curators of the collection, which is kept in Milan's Sforzesco Castle, said it had been studied by many well-qualified scholars in the past and none had claimed to have identified Caravaggios. They said the two art historians who made the claim had only studied photographic reproductions of the drawings, not the originals. Francesca Rossi, the current curator of the collection, said: "We were in contact with them a year ago when they asked for photographic reproductions but I've never seen them here. These are generic drawings, it is impossible to be certain (that they are by Caravaggio). The attribution seems overly ambitious and not very credible. "I'm very perplexed," Maria Teresa Fiorio, the former director of the castle's collection, told Corriere della Sera. A serious scholar doesn't produce an e-book - they would publish their findings in the appropriate journals. Everyone who has studied the collection has asked themselves - is it possible that some were drawn by Caravaggio? No one has drawn that conclusion. The director of the castle collection, Claudio Salsi, also said the art historians' conclusion was "without critical foundation." Francesca Cappelletti, who a decade ago helped identify a painting owned by the Jesuits in Dublin as a long-lost Caravaggio, said: "To me they still look like typical drawings by Peterzano." Other experts said they would keep an open mind until further research was carried out. "We must be very prudent," said Cristina Terzaghi, an art historian at the University of Rome III and the author of a book on Caravaggio. Their research must be carefully studied and verified by the scientific community. But the art historians stood by their claim. They said they had set out to solve the "mystery" of Caravaggio's earliest artistic development. When Caravaggio moved from Milan to Rome, where he was to achieve fame and notoriety, he took with him a "sort of mental suitcase" of drawing and painting techniques which he later refined into his famous chiaro-oscuro technique of contrasting light and darkness, said Mr Bernadelli Curuz. If you go digging around in Italy's incredibly rich cultural heritage, it is still possible to find extraordinary things.