When is a Caravaggio not a Caravaggio?

Once Caravaggio was known to have been a fast painter, is it not possible that there are paintings which have not yet been recognised as his work?

This is one of the questions that often crosses the minds of scholars when they come to assess works that feature the chiarascuro technique and raw realism that were two of Caravaggio's trademarks.

Sandro Debono, the senior curator in charge of arts at Heritage Malta, said in an interview that until the 1950s, Caravaggio was considered only as an important artist and not as the wonder painter he is feted as today. It was art historian and critic Roberto Longhi who unveiled to the world, during an exhibition in Milan, Italy, the great power that lies bubbling in Caravaggio's paintings.

"Even Longhi believed at one time that the portrait of Grand Master Alof de Wignacourt now housed at the Louvre, in Paris, was not a Caravaggio.

"Several paintings that originally were considered copies eventually ended up being considered as authentic Caravaggios. There were cases where scholars considered a work to be by the master painter and others that were not and vice versa," Mr Debono said.

In fact, the upcoming Heritage Malta exhibition Caravaggio: L'Immagine Del Divino is meant to spur debate by featuring two paintings showing two versions of a St Francis in meditation.

One had been considered an original Caravaggio since the early 20th century until the second version was identified in the late 1960s.

The debate was concluded in 2000 thanks to a joint conservation project on both paintings. It was then revealed that the version identified in the late 1960s was after all the authentic Caravaggio and not the one considered unanimously as a Caravaggio for decades.

The exhibition will be held between the end of this month and the end of November, with 10 original works by the great Italian maestro and another which is deemed to be not a Caravaggio.

The event forms part of the activities being organised by the national cultural agency marking the 400th year of Caravaggio's short interlude on the island.

The international standing of the exhibition is evident by the illustrious names of its curators: Sir Dennis Mahon and Maurizio Marini.

Sir Dennis is a renowned art historian and collector who is, at times, described as the dean of world experts while Mr Marini is a Caravaggio specialist.

Sir Dennis was the art historian to have single-handedly re-assessed 17th century Italian art. The many paintings he acquired as bargains he later donated to public museums. "On his part, Mr Marini has been proposing that the San Giovannino at Galleria Corsini in Rome, which is a mirror image of the St Jerome at the Oratory of the Co-Cathedral of St John, in Valletta, could have possibly been painted in Malta, basing his assertion on the similarity between the two works.

"On the other hand, both Marini and Mahon are putting forward the theory that Caravaggio repeated himself in various works. This is taken to mean that the artist repeated the same composition all over again from memory or with little help.

"This must have surely been a great feat knowing that no preparatory drawing by Caravaggio survives since he would apparently work directly on the canvas," Mr Debono said.

The exhibition will also help the viewer piece together a picture of what Malta was going through during the time Caravaggio was here between June 1607 and October 1608.