A new and not very subtle weapon is helping art collectors in the battle against forgers: the Bomb.

Russian scientists believe that nuclear test explosions and the bombs dropped on Japan in 1945 released elements into the atmosphere that can be detected in oil paintings made after the Second World War. The technique has been patented and is being used by Russian collectors to test prospective purchases.

Elena Basner, a former curator at the Russian Museum in St Petersburg who developed the method, claims that it provides indisputable evidence of whether a painting was made before or after 1945. British art specialists welcomed the breakthrough yesterday, saying that it would help to tackle the increasingly elaborate fakes flooding the international art market.

Johnny Van Haersten, an art dealer in St James’s, Central London, specialising in Dutch Old Master paintings, said: “It will be extremely useful, particularly for modern pictures where forgeries are becoming more prevalent and much more sophisticated.”

Dr Basner told The Art Newspaper that the idea came to her while working at the Russian Museum between 1978 and 2003. A curator of 20th-century art, she spent much of her time attempting to authenticate works.

“I noticed that forgers already had all the angles covered, and could perfectly reproduce the paints, canvas etc, so I wanted to find something iron-clad in these paintings that could not be disputed, and this led me to approach scientists for ideas.”

They concluded that the split atom was the single most important difference between the periods before and after the Second World War.

The first nuclear bomb was successfully tested in July 1945 in New Mexico. On August 6, 1945, an atomic bomb was dropped on Hiroshima and three days later a second, more powerful bomb was dropped on Nagasaki. About 550 further explosions were carried out by the United States, Britain, the Soviet Union and France before most countries signed the Limited Test Ban Treaty in 1963. China tested its first Bomb the next year.

Dr Basner’s team argue that this activity released isotopes into the environment that do not occur naturally. Tiny traces of these isotopes, caesium-137 and strontium-90, permeated soil and plant life and ended up in all postwar paintings through the natural oils used as binding agents for paints.

Any work of art purporting to be more than 63 years old that registers trace amounts of the two isotopes can therefore be definitively declared a fake, Dr Basner said.

Andrei Krusanov, a geochemist and art historian who has written books on the Russian avant-garde, said: “There cannot be any other way around it. Any oil painting made in the nuclear era will show traces of caesium-137 and strontium-90.”

Dr Basner, who is a consultant to a Swedish auction house, plans to use the technique to test the authenticity of Russian avant-garde works dating from 1900 to 1930. “The number of avant garde fakes out there is unbelievable, probably more than the number of genuine works,” she said.

“Collectors and dealers do not want to come to us. They are afraid the market will resist this technology. There are many people who have an interest in keeping fakes in circulation.”

While the technology might be able to identify a forgery, it cannot definitively prove that a work is genuine. Antonia Kimbell, of the Art Loss Register, an organisation that helps to tackle art crime, said that dating the paint was a very good starting point to an investigation but it would not be the deciding factor.

Some forgers, such as Robert Thwaites, who was caught forging 19th-century paintings in 2004, use paints and canvasses from the relevant period, which would enable them to circumvent isotope analysis. “You would have to look at other factors,” Ms Kimbell said. “Provenance is the most important, although this can and has been faked too.”

20th-century frauds

— John Myatt was said to be the greatest 20th-century faker. He was jailed in the 1990s but now has a legitimate artistic career

— A New York art dealer called Ely Sakhai was convicted of fraud in 2004 after identical “Gauguin” works appeared at rival auctions

— Elmyr de Hory, a Hungarian, claimed to have forged a thousand works by Chagall, Matisse and other modern masters

— Eric Hebborn, a dashing British forger of artists including Rubens, Bruegel, Van Dyck, Corot and Augustus John, wrote a hit memoir

— Picasso, told that he had condemned as a fake one of his own genuine works, responded: “Sometimes I fake Picassos”

Source: Times database

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