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PARIS - Five hundred and seventy-five years after she was convicted by an English court of witchcraft and heresy before being burned at the stake, Joan of Arc faces another trial - by science.
Initial results from the most rigorous lab assessment ever made of the relics of France's teenage warrior and patron saint suggest the revered bones could be bogus.
"The chances are diminishing that these are the remains of the French heroine," says Philippe Charlier, a forensic scientist and specialist in historical pathology.
"Based on past experiences with relics that are often false, my thoughts prompt me to think we are heading towards the conclusion that this is a fake relic."
Charlier's 18-member team spent six months testing scorched-looking bones, including a 15cm chunk of rib, and a piece of linen.
According to repute, these items were recovered from the pyre where Joan was executed in the Normandy town of Rouen on May 30, 1431.
Owned by the Archdiocese of Tours, which houses them in a museum at Chinon, the relics are said to be the only surviving physical link with the Maid of Orleans who led the revolt against the English.
But microscopic and chemical tests now show that the bones were not burned.
Their dark coating is of some vegetal and mineral substance, which the scientists believe was probably something used in embalming.
The cloth does, however, appear to date from the 15th century, but turns out to have been dyed a dark colour, and was not burned, according to their preliminary report.
"It could be that these are human remains of the 15th century which were treated to a sort of embalming process or protective treatment, which was the case when relics were handled, says Charlier, a forensic scientist at the Raymond Poincare Hospital in Garches.
"But in any case, we know that Joan of Arc was not embalmed."
An illiterate peasant girl born in 1412, Joan responded to "divine voices" in her head by rallying the forces of Charles VII against England's domination of northern France.
She was eventually caught by Burgundian soldiers - Burgundy being an English ally at the time - and handed over to the English. After a show trial in Rouen, the headquarters of the English occupation, she was burned at the stake.
Determined to forestall any rumours that she might have escaped - and also to prevent her remains from becoming an object of veneration - the English burned the body twice more to reduce it to ashes, and the executioner, Geoffrey Therage, was ordered to cast her remains into the River Seine.
The relics enter the historical record in the 17th century, in an apothecary's shop in Paris' Faubourg Saint-Antoine. They reputedly had been picked from the pyre's remains and handed from generation to generation and from family to family.
In 1867, they were turned over to the bishop of Tours. In 1909, scientists declared it "highly probable" that the relics were authentic. That same year, Joan was beatified, and canonisation followed in May 1920.
Despite the blow to authenticity, not everything is lost for the bones' believers. One bone turns out to be a cat's femur - and this, paradoxically, adds to the claim's credibility. Charlier notes that, in mediaeval times, cats, symbolising the devil, would sometimes be thrown into the pyres to dispel satanic influence.
