The Turin Shroud is far older than carbon dating suggests and may indeed date to biblical times as believers claim, a study has found.

　　The findings may revive hopes that the cloth, far from being a medieval fake, is a miraculous recording of the face of Jesus after the Crucifixion. Raymond Rogers, of the University of California's Los Alamos Laboratory, argues that carbon-dating tests on the shroud in 1988 were "invalid" because they were performed on a replacement section rather than the original linen. His own exhaustive tests, most of them chemical analyses of fibres he says were taken from the original linen, instead reveal its age to be from 1,300 to 3,000 years old.

　　Many Roman Catholics, who believe the cloth bears the image of Jesus after it was used to wrap his body when he was taken from the Cross, were incensed by the results of the first scientific tests.

　　Researchers, working separately in Arizona, Cambridge and Zurich, carried out tests which concluded that the shroud could be dated only to between AD 1261 and 1390, and was therefore likely to be a deception devised in the Middle Ages.

　　Even the then cardinal of Turin, Anastasio Alberto Ballestrero, was forced to concede that the garment was probably a hoax.

　　However, writing in the journal Thermochimica Acta, Mr Rogers explains that fibres from the original linen showed no trace of a chemical called vanillin. Vanillin is produced by the thermal decomposition of lignin, a chemical compound found in plant material such as flax. Levels of lignin in material such as linen fall over time.

　　Had the shroud been produced in medieval times it would still contain vanillin. Mr Rogers, a member of the original Shroud of Turin Research Project which first began studying the linen in 1978, wrote of his surprise at the findings of the radio-carbon dating a decade later.

　　After re-examining the data, he concluded that the sample used for dating in 1988, and the other 32 samples he had personally taken of the linen fibre from all over the four-yard shroud, using adhesive tape, were not the same.

　　Chemical kinetics, analytical chemistry, and other tests, including some for cotton content, proved, he said, that the "radio-carbon sample was not part of the original cloth", and so was "invalid in determining the age of the shroud". According to the academic, the cloth used in the carbon dating was probably woven into the shroud during repairs in late medieval times. The linen sheet was damaged in several fires after its existence was first recorded in France in 1357, including in a church blaze in 1532.

　　It was also been treated with alizarin dye, available in Italy only after the 1300s, and with a plant gum to help match the original's sepia colour.