UN atomic watchdog: nuclear detective not only for weapons but on damaged art, too

The United Nations atomic watchdog agency, better known around the world for its efforts to curb nuclear proliferation and stop weapons of mass destruction from falling into the hands of terrorists, is helping an Austrian museum assess damage and identify ways to preserve a stolen Renaissance sculptural masterpiece that was recently recovered.

Acting as a nuclear detective in a little known sphere, the UN International Atomic Energy Agency (IAEA) has loaned Vienna’s Kunsthistorisches (Art History) Museum an instrument known as X-ray fluorescence spectroscopy (or XRF) to examine and uncover hidden truths about a golden salt and pepper cellar sculpted by Benvenuto Cellini, which was found buried deep in a forest after being stolen in 2003.

Just under 30 centimetres high, the Saliera – sculpted in the 16th century to hold spices for royal feasts – shows the graceful bodies of a man and woman symbolizing the god of the sea and goddess of earth. Its value exceeds $60 million.

Not many people know that nuclear-based techniques like XRF are used for studying works of art, from Cellini’s Saliera to Michelangelo’s David. But they have proved their worth in fields ranging from art restoration to archaeology and the preservation of cultural artifacts.

The best feature is that the invisible rays do not destroy or harm the treasured art. Another is its portability. Since any movement to a work of art is potentially catastrophic, the goal of art restorers is to minimize disturbance. And XRF, about the size of an overhead projector mounted on a moveable chassis, can be brought right to the source.

As it was to unlock the secrets of Cellini’s Saliera. Initial findings show that the gold is very pure, about 90 per cent. The composition of the sensitive, partly flaking enamel that covers the masterpiece is still being examined. Martina Griesser, who heads the museum’s conservation science department, said the enamel had been degrading over time but “the theft certainly did not help things.”

Having the sculpture exposed to harsh elements is a horrifying scenario for museum conservators. “The theft damaged the Saliera but fortunately not so much as we were expecting,” Ms. Griesser said.

Most obvious is a deep scratch at the breast of the female figure, probably caused by the crowbar the thief used to smash the showcase it was stored in. The information obtained from the XRF gives conservators like Helene Hanzer the best chance to restore the piece and protect it for the future. With the help of XRF, it is hoped that the Saliera will be fully restored and back on public display in 2008.

Apart from its nuclear weapons remit, the IAEA has a multi-dimensional mission that crosses a host of fields from medical diagnosis and cancer treatment to isotope tracking of underground water to weather and climate studies.