Carbon dating art
These included an article by American chemist Raymond Rogers, who conducted chemical analysis for the Shroud of Turin Research Project and who was involved in work with the Shroud since the STURP project began in 1978.
Rogers took 32 documented adhesive-tape samples from all areas of the shroud and associated textiles during the STURP process in 1978. Luigi Gonella (Department of Physics, Turin Polytechnic University) on 14 October 1979, which Gonellla told him were from the Raes sample.
group published the list of tests to be performed on the shroud; these aimed to identify how the image was impressed onto the cloth, to verify the relic's purported origin, and to identify better-suited conservation methods. We are faced with actual blackmail: unless we accept the conditions imposed by the laboratories, they will start a marketing campaign of accusations against the Church, which they will portray as scared of the truth and enemy of science.
lack of blindness in the measurements is a rather insubstantial reason for disbelieving the result." (t)he Church must respond to the challenge of those who want it to stop the process, who would want us to show that the Church fears the science.
The blind-test method was abandoned, because the distinctive three-to-one herringbone twill weave of the shroud could not be matched in the controls, and it was therefore still possible for a laboratory to identify the shroud sample.
group expected to perform the radiometric examination under its own aegis and after the other examinations had been completed, while the laboratories considered radio-carbon dating to be the prime test, which should be completed at the detriment of other tests, if necessary.
that radio-carbon testing dated the shroud to a date of 1260-1390 CE, with 95% confidence.
Luigi Gonella claimed to have taken from the radiocarbon sample before it was distributed for dating.
The actual provenance of these threads is uncertain, as Gonella was not authorized to take or retain genuine shroud material, Raymond Rogers stated in a 2005 article that he performed chemical analyses on these undocumented threads, and compared them to the undocumented Raes threads as well as the samples he had kept from his STURP work.
He stated that his analysis showed: "The radiocarbon sample contains both a gum/dye/mordant coating and cotton fibers.
The remaining sample, measuring 81 mm × 16 mm (3.19 in × 0.63 in) and weighing 300 mg, was first divided in two equal parts, one of which was preserved in a sealed container, in the custody of the Vatican, in case of future need.
The other half was cut into three segments, and packaged for the labs in a separate room by Dr Tite and the archbishop.The lab representatives were not present at this packaging process, in accordance with the protocol.