After hearing comments there and after rereading some material, especially Ian Wilson’s chapter "Carbon Dating: Right or Wrong" in his 1998 book The Blood and the Shroud, I’m becoming more and more convinced that another C-14 test would be unwise and moreover, that the Shroud is simply not, and never has been, a suitable item to carbon date.
Wilson points out in his book (pp. 190-191) that in the 1960s, 2 Harwell lab scientists warned Vera Barclay, a British proponent of having the Shroud carbon dated, of pitfalls.
Dr. J.P. Clarke told Barclay,
There appears to be some doubt as to whether the carbon content of the material has remained constant over the years. It would be an assumption of any dating that the addition of something at a date later than that of the fabrication of the Shroud.
P.J. Anderson told her:
The history of the Shroud does not encourage one to put a great deal of reliance upon the validity of any C14 dating. The whole principle of the method depends upon the specimen not undergoing any exchange of carbon between its molecules and atmospheric dioxide, etc. The cellulose of the linen itself would be good from this point of view, but the effect of the fires and subsequent drenching with water . . . and the possibility of contamination during early times, would, I think, make the results doubtful. Any microbiological action upon the Shroud (fungi, moulds, etc., which might arise from damp conditions) might have important effects upon the C14 content. This possibility could not be ruled out
Wilson himself goes on to say:
That such concerns have been far from eliminated by more modern methods is quite evident from a recent booklet by Dr Sheridan Bowman, Michael Tite’s successor as Keeper of the British Museum’s Research Laboratory, in which she lists the sorts of conservation and packing materials that archaeologists should avoid using when sending their samples for processing by a radiocarbon-dating laboratory: ‘Many materials used for preserving or conserving samples may be impossible to remove subsequently: do not use glues, biocides . . . [etc.] Many ordinary packing materials such as paper, cardboard, cotton, wool and string contain carbon and are potential contaminants. Cigarette ash is also taboo.’ It is worth reminding ourselves here of the variety of already listed carbon-containing materials with which the Shroud maintains daily contact, e.g., a sixteenth-century holland cloth, a nineteenth-century silk cover – quite aside from the innumerable candles that have been burnt before it, the water that was thrown over it at the time of the 1532 fire, and so on. And those are merely the events we know about.
One other excerpt worth noting here (pg 193):
Archaeologists, who routinely call upon radiocarbon-dating laboratories’ services, tend to shy from openly criticising the results they receive, even if they do not necessarily agree with some of them, but one who certainly has no qualms is Greece’s Spyros Iakovidis, speaking at an international conference in 1989: ‘In relation to the reliability of radiocarbon dating I would like to mention something which happened to me during my excavation at Gla [in Boeotia, Greece]. I sent to two different laboratories in two different parts of the world a certain amount of the same burnt grain. I got two readings differing by 2000 years, the archaeological dates being right in the middle. I feel that this method is not exactly to be trusted.’ [Italics in original]
Because of such opinions–and keep in mind the above ones are by people who actually used the C-14 technique, it was all the more unfortunate and detrimental that the C-14 test wasn’t at least done as one of many other tests at the same time. Those other tests may have provided overwhelming evidence that the Shroud was from the 1st century, and since it’s not uncommon for C-14 dates to be disregarded in some instances***, there would not be as much ink being spilled on the Shroud C-14 results.
If another C-14 test is ever done, it will take a lot more background study, and hopefully it wouldn’t be done in isolation from other multi-disciplinary testing.
***Rogue dates are common in archaeology and geology . . . Such has been my experience as an archaeologist who has excavated, submitted and interpreted more than one hundred carbon 14 samples from Neolithic, Bronze Age and Early Historical sites. Of these dates obtained, 78 were considered credible, 26 were rejected as unreliable and 11 were problematic. I mention this merely to inform the non-specialist . . . —William Meacham, archaeologist, Centre of Asian Studies,University of Hong Kong, 2000
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