Sources of error in radiocarbon dating
The three control samples, the approximate ages of which were made known to the laboratories, are listed below. T/32) from a tomb excavated at Qasr Ibrîm in Nubia by Professor J. This linen was dated in the British Museum Research Laboratory using liquid scintillation counting, giving a radiocarbon age of 2,010 ± 80 yr BP (BM-2558).Two were in the form of whole pieces of cloth (samples 2 and 3) and one was in the form of threads (sample 4). This corresponds to a calendar age, rounded to the nearest 5 years, of 110 cal BC - AD 75 cal at the 68 per cent confidence level (where cal denotes calibrated radiocarbon dates). Threads removed from the cope of St Louis d'Anjou which is held in a chapel in the Basilica of Saint-Maximin, Var, France.Testore of Department of Materials Science, Turin Polytechnic and G. If the samples had been unravelled or shredded rather than being given to the laboratories as whole pieces of cloth, then it would have been much more difficult, but not impossible, to distinguish the shroud sample from the controls.
The size of the sample then required, however, was ~500cm, which would clearly have resulted in an unacceptable amount of damage, and it was not until the development in the 1970s of small gas-counters and accelerator-mass-spectrometry techniques (AMS), requiring samples of only a few square centimetres, that radiocarbon dating of the shroud became a real possibility. The shroud was separated from the backing cloth along its bottom left-hand edge and a strip (~10 mm x 70 mm) was cut from just above the place where a sample was previously removed in 1973 for examination.Following this intercomparison, a meeting was held in Turin in September-October 1986 at which seven radiocarbon laboratories (five AMS and two small gas-counter) recommended a protocol for dating the shroud. The samples were then taken to the adjacent Sala Capitolare where they were wrapped in aluminium foil and subsequently sealed inside numbered stainless-steel containers by the Archbishop of Turin and Dr Tite.In October 1987, the offers from three AMS laboratories (Arizona, Oxford and Zurich) were selected by the Archbishop of Turin, Pontifical Custodian of the shroud, acting on instructions from the Holy See, owner of the shroud. Samples weighing 50 mg from two of the three controls were similarly packaged.The results provide conclusive evidence that the linen of the Shroud of Turin is mediaeval.The Shroud of Turin , which many people believe was used to wrap Christ's body, bears detailed front and back images of a man who appears to have suffered whipping and crucifixion.