New dating technique could establish age of the Turin Shroud

This is an article that I was commenting on at Dan Porter's Shroud of Turin Blog, when I decided to post it with my comments here on my own blog! My comments are bold to distinguish my words from the article's.

[Above (click to enlarge): Diagram including Texas A&M's plasma chamber: Tabacaru, G., et al., "The Light Ion Guide CB-ECRIS Project at the Texas A&M University Cyclotron Institute," Proceedings of ECRIS08, pp.194-197, p.195. Note the plasma chamber's very small size.]

"New dating technique could establish age of the Turin Shroud," Telegraph.co.uk, Richard Alleyne, Science Correspondent, 24 Mar 2010 ... The Turin Shroud could finally be dated accurately thanks to new technique that determines the age of ancient artefacts without damaging them, claim scientists. This tacitly admits that the Shroud was not "accurately dated" in 1988 (see further below)!

See also the same story at: "Could new test settle Shroud of Turin debate?," Discovery News, March 24, 2010; "Researchers Introduce `Non-Destructive' Carbon Dating" Scientific Blogging, March 23rd 2010; "New Method Could Revolutionize Dating of Ancient Treasures," ScienceDaily, March 23, 2010 & "Method would `revolutionize' dating of ancient treasures," World Science, March 23, 2010.

The researchers said the new method was so safe it could allow scientific analysis of hundreds of artefacts that until now were off limits because museums and private collectors did not want the objects damaged. For those who are new to the Shroud and/or radiocarbon-dating, a major limiting factor in radiocarbon-dating the Shroud of Turin, or any priceless artifact, is that the sample must be reduced to carbon by burning it, which totally destroys that part of the artifact (see below).

"This technique stands to revolutionise radiocarbon dating," said Dr Marvin Rowe,

[Right: Dr. Marvin Rowe: Professor Emeritus, Texas A&M University.]

who led the research team at the Texas A&M University. It expands the possibility for analysing extensive museum collections that have previously been off limits because of their rarity or intrinsic value and the destructive nature of the current method of radiocarbon dating. "In theory, it could even be used to date the Shroud of Turin." This last is highly significant coming from a senior Professor in the field of radiocarbon-dating archaeological artifacts, as Dr Rowe is. That is because it is a tacit admission by him of what is probably now widely accepted in the radiocarbon-dating community, that the 1988 carbon-14 dating of the Shroud as "AD 1260-1390 ... mediaeval":

"The results of radiocarbon measurements at Arizona, Oxford and Zurich yield a calibrated calendar age range with at least 95% confidence for the linen of the Shroud of Turin of AD 1260 - 1390 (rounded down/up to nearest 10 yr). These results therefore provide conclusive evidence that the linen of the Shroud of Turin is mediaeval." (Damon, P.E., et al., "Radiocarbon Dating of the Shroud of Turin," Nature, Vol. 337, 16 February, 1989, pp.611-615, p.614).

was flawed, otherwise why bother proposing to radiocarbon-date the Shroud again?

Traditional carbon dating involves removing and burning small samples of the object. Scientists remove a small sample from an object, such as a cloth or bone fragment. Then they treat the sample with a strong acid and a strong base and finally burn the sample in a small glass chamber to produce carbon dioxide gas to analyse its C-14 content. Although it sometimes requires taking minute samples of an object, even that damage may be unacceptable for some artefacts. The Shroud could still be radiocarbon-dated conventionally by taking tiny samples of a few threads each from several different inconspicuous areas (e.g. under the side-strip's seam, at the sheet's ends and sides, etc) with no significant visual loss or risk (see next) to the Shroud itself. In fact, even the charred areas from the 1532 fire, that were removed in the 2002 restoration and have been kept, could be carbon-dated, with no loss to the Shroud, whatsoever:

"A significant amount of charred cellulose was removed during a restoration of the shroud in 2002. Material from different scorch locations across the shroud was saved in separate containers. The elemental carbon could be completely cleaned in concentrated nitric acid, thus removing all traces of foreign fibers, sebum from repeated handling, and adsorbed thymol from an unfortunate procedure to sterilize the shroud's reliquary in 1988. In addition, the separate samples would give a `cluster' of dates, always a desirable procedure in archaeology. A new radiocarbon analysis should be done on the charred material retained from the 2002 restoration." (Rogers, R.N., 2005, "Studies on the radiocarbon sample from the shroud of turin," Thermochimica Acta, 425, pp.189–194, pp.193–194).

The new method does not involve removing a sample of the object. Scientists place an entire artefact in a special chamber with a plasma, an electrically charged gas similar to gases used in

[Above (click to enlarge): University of Arizona's similar plasma oxidation chamber for radiocarbon-dating: Jones, K.B., et al., "A new plasma oxidation apparatus for radiocarbon dating," University of Arizona, October 1, 2005]

big-screen plasma television displays. The gas slowly and gently oxidises the surface of the object to produce carbon dioxide for C-14 analysis without damaging the surface, he said. As I commented on Dan Porter's blog (with corrections):

"I cannot imagine that the Roman Catholic Church would ever allow the entire Shroud to be placed in a chamber of gas which is then electrically charged up to a plasma state. Nor should us Shroudies want them to take the risk, if there was even the slightest chance that something could go wrong and the Shroud be destroyed or permanently changed (e.g. the image disappear into the background). I personally do not want to gain a 1st century radiocarbon dating of the Shroud but lose it in the process."

and:

"... there is effectively zero probability that the Pope would allow the whole Shroud to be put in a chamber of gas which was then electrically charged up to a plasma state."

This was confirmed by what I later read, "it would take a significant amount of data to convince museum directors, art conservators and ... the Vatican that the ... method ... causes no damage":

".... Rowe and his colleagues ... conceded, however, that it would take a significant amount of data to convince museum directors, art conservators and possibly the Vatican that the non-invasive method indeed causes no damage." (Lorenzi, R., "Could new test settle Shroud of Turin debate?," Discovery News, March 24, 2010).

The problem is, as I commented above, there would always be a possibility of something going wrong, and the artifact being damaged or destroyed. I predict that few (if any) museum directors (let alone the Vatican) would consider that the risk, no matter how small, of losing one of their priceless artifacts, is worth knowing more precisely how old it is.

Anyway, having now seen how small the plasma chambers are in the above diagram of Texas A&M's and photos of the University of Arizona's, and reading another article on this "small ivory figurine called the `Venus of Brassempouy'" which "is small enough to fit into the chamber used for analysis" and that, "The chamber" would have to "be sized to accommodate large objects, such as ... the Shroud of Turin":

"The chamber could be sized to accommodate large objects, such as works of art and even the Shroud of Turin, which some believe to be the burial cloth of Jesus Christ, Rowe said. He acknowledged, however, that it would take a significant amount of data to convince museum directors, art conservators, and others that the new method causes no damage to such priceless objects The scientists are currently refining the technique. Rowe hopes to use it, for instance, to analyze objects such as a small ivory figurine called the `Venus of Brassempouy,' thought to be about 25,000 years old and one of the earliest known depictions of a human face. The figurine is small enough to fit into the chamber used for analysis." ("New Method Could Revolutionize Dating of Ancient Treasures," ScienceDaily, March 23, 2010)

I realised that it is not currently possible to date the Shroud using this method, and it remains to be seen if it ever will be.

Dr Rowe and his colleagues used the technique to analyse the ages of about 20

[Right: Venus of Brassempouy: Wikipedia, 24 March 2010. Note this figurine's tiny size: "She is 3.65 cm high, 2.2 cm deep and 1.9 cm wide" or 1.44 x 0.87 x 0.75 inches.]

different organic substances, including wood, charcoal, leather, rabbit hair, a bone with mummified flesh attached, and a 1,350-year-old Egyptian weaving. The results match those of conventional carbon dating techniques, they say. The chamber could be sized to accommodate large objects, such as works of art and even the Shroud of Turin, which some believe to be the burial cloth of Jesus Christ, Dr Rowe said. Again, why would Dr Rowe even bother to date "the Shroud of Turin" by this method if the 1988 radiocarbon dating had provided "conclusive evidence that the linen of the Shroud of Turin is mediaeval"? Presumably he knows it didn't.

The origins of the shroud and its image are the subject of intense debate among scientists, theologians, historians and researchers. Some contend that the shroud is the cloth placed on the body of Jesus Christ at the time of his burial, and that the face image is the Holy Face of Jesus. The evidence is overwhelming that the Shroud of Turin is the burial sheet of Jesus!

Others contend that the artefact postdates the Crucifixion of Jesus by more than a millennium. They are simply wrong. The only evidence that the Shroud "postdates the Crucifixion of Jesus by more than a millennium" is the 1988 radiocarbon-dating and that has been found to be wrong because what was dated was a medieval patch, not the Shroud itself:

"Radiocarbon 14 dating of the Shroud of Turin ... Once generally accepted by the scientific community by those who consider the shroud to be inauthentic, and by some members of the Catholic Church, these results have since been questioned in peer-reviewed journals by Raymond Rogers in Thermochimica Acta and by M.Sue Benford and Joseph G. Marino in Chemistry Today. Criticisms have been raised about aspects of the study as doubts were raised regarding the original nature of the sample that was taken for testing, not the quality of the radiocarbon testing itself." ("Shroud of Turin: Radiocarbon dating," Wikipedia, 31 March 2010. Footnotes omitted).

Moreover, a thread from the Shroud itself has been radiocarbon-dated at "about AD 200" (my emphasis)!:

"A very interesting finding is that a single weft thread has been extracted at about the midway level of where the Raes sample was removed, beginning about 1 cm medial to the rolled seam that reattached the Shroud to the backing cloth. The space of the missing thread appears to be about 8 cm in length. We do not know the history of this particular thread, but Dr. Alan Adler had a thread about 8 cm in length that came from the Shroud that he acquired in the early 1980s from an unidentified source. He detected what he referred to as starch on one end of this thread. He then had a very unofficial and admittedly inadequate radiocarbon dating done on each end of this thread in 1983. Reportedly, the starched end tested about AD 1000 and the other end of the same thread tested about AD 200. At a minimum, this would indicate that carbon dating the Shroud might be very technically problematic. Assuming that the thread that Dr. Adler had might have been the one that had been extracted at this site, we may have a highly significant, even if inadequate, finding, since the lateral 1 to 2 cm of this thread would have been in the continuation of the area from which the 1988 specimen was extracted. If this scenario is correct, we may not only have evidence that the 1988 sample-extraction-area is abnormal, but we may also have a much more accurate dating of the body of the Shroud, namely, in the range of AD 200." (Whanger A.D. & Whanger, M., 2005, "Excerpt from Radiological Aspects of the Shroud of Turin," Council for Study of the Shroud of Turin: Durham NC, pp.1-15, p.5).

[Left: Missing 8 cm thread near where the Raes' sample was taken, which is presum- ably the 8 cm thread that the late Dr. Alan Adler had privately carbon-dated in 1983, and which returned a date at one end of AD 1000 and at the other end AD 200: Figure 19 in Whanger & Whanger, 2005, "Excerpt from Radiological Aspects of the Shroud of Turin," p.15.]

And since contamination by newer carbon-14 (e.g. by human handling, microbe and fungal invasion, smoke, etc) makes an artifact's radiocarbon age appear more recent than it actually is, a radiocarbon dating of AD 200 is consistent with the linen of the Shroud dating from the time of Jesus!

Posted 1 April 2010. Updated 19 December 2023