Frankly, I’m a little surprised that the news that the Shroud has at last been definitively proven to be from the time of Christ has received considerably less publicity than the discovery that it is actually a tablecloth made in Burton-on-Trent, or the idea that Jesus didn’t die from crucifixion, but by rupturing blood vessels in his shoulder when he fell over on the way to Golgotha. I’ll discuss possible reasons for that later, but for the moment, let’s look at the two papers that contribute to the latest ‘time of Christ’ claim.
They are ‘X-Ray Dating of Ancient Linen Fabrics,’ Liberato de Caro et al., Heritage Journal, November 2019, and ‘X-Ray Dating of a Turin Shroud’s Linen Sample,’ Liberato de Caro et al., Heritage Journal, April 2022. Although the co-authors are mostly colleagues of de Caro’s at the Istituto di Cristallografia, Consiglio Nazionale delle Ricerche (IC-CNR), in Bari, Italy, the last named in both papers, Giulio Fanti, firmly nails their colours to the authenticist mast.
The premise is simple enough, and not at all improbable; that cloth deteriorates with age, mostly by oxidation, under conditions of temperature and humidity, and that, other things being equal, this deterioration might be measured and calibrated, giving us a possible method of dating textiles without recourse to radiocarbon dating.
We have been here before, and, as we shall see, the new findings are closely related to the previous ones. However, although “alternative dating techniques have contradicted the radiocarbon findings” is a popular trope among podcasters, the earlier experiments have not found much favour among mainstream sindonologists, for sensible reasons, in particular due to the selection of materials and the statistical manipulation that was necessary for the ‘correct’ conclusion to be drawn.
So let’s start at the very beginning (a very good place to start), and Giulio Fanti’s paper, ‘Multi-parametric Micro-mechanical Dating of Single Fibers coming from Ancient Flax Textiles,’ published in Textile Research Journal in 2014. His idea was that flax fibres get weaker as they get older, so all he had to do was to test the strength of a selection of fibres from textiles of different known ages, draw up a calibration graph, and then any unknown fabric could have its strength measured and its date discovered.
However, the first thing was to acquire representative fibres from different dates. Numerous samples were considered, from which a suitable list of nine were chosen, plus two modern pieces, one bleached and one ‘raw.’ “A preliminary analysis based on visual inspection by means of a stereo microscope was performed, so as to select only samples suitable for the tests.” For example, “the flax sample of a shroud, recently discovered in Akeldama cave in Jerusalem, was not chosen for the analysis because the relatively moist environment of Jerusalem accelerated the deterioration process: this was clearly visible at the first inspection both because [of] its blackish colour and in the difficulty of handling the very fragile threads.”
Fabrics having been chosen, individual fibres were painstakingly extracted and mounted on testable tabs, and then closely inspected for a) discolouration and b) obvious structural defects such as micro cracks. Then the fibres were given a quick bend to check for c) ‘macroscopic anomalies,’ and those that survived that could also be rejected during the experimentation for d) ‘an evident anomalous stress-strain curve’ and e) results too far from the average of all the results for any particular textile.
The numbers of fibres that finally contributed to that first experiment are shown below:
Before moving on, we may pause to consider the code numbers. Were there originally more fabrics – from C to L, say, some possibly repeated, as in C, CI and CII? The paper does not say. We also note that the four fibres from the Qarantal Cliff textile all passed muster, while none of the 22 fibres from Peru did. Fabric A was also not, in fact, used in the subsequent investigation, as it was thought that bleaching may well have damaged the fibres.
The first of a battery of five mechanical tests was for breaking strength, and these are the results:
Once again, let’s pause for consideration. Although we may discern a broad, roughly linear trend from top right to bottom left, we must ask ourselves how to account for the fact that three samples of fabric, chronologically spaced about 1500 years apart, all required about 55 MPa to break them. None of the fibres tested were discoloured or obviously damaged, or had anomalous stress-strain curves, yet the Fayyum fibres, which should have sustained 200-300 MPa, actually broke after 65 MPa or so, and one of the Egyptian samples, which should have broken at 2 MPa, in fact lasted until 60 MPa. We might speculate that the Egyptian sample was cold, or that the Fayyum sample was damp, but speculation is all it can be.
This first paper was quickly followed by a second, ‘Mechanical and Opto-chemical Dating of the Turin Shroud,’ published as part of the proceedings of the Workshop Of Paduan Scientific Analysis on the Shroud, in 2015. Representative fibres from the Shroud were tested, and had a breaking strain of 243 MPa, roughly double what it should have sustained as a first century textile, and half what it should have sustained if medieval. Depending on one’s predisposition, one might speculate that the fabric had been kept particularly warm and dry (if authentic), or that the damp and cold of Europe made it deteriorate faster than predicted by the other fabrics, all from the hot, dry deserts of the Middle East. We might also remember that “the relatively moist environment of Jerusalem” would have “accelerated the deterioration process,” which is why the Akeldama shroud, more or less contemporary in time and place, was originally rejected.
Now let’s move on to WAXS. In 2020, the IC-CNR team in Bari published a paper called ‘Wide Angle X-Ray Scattering [the WAXS of the title] to Study the Atomic Structure of Polymeric Fibers,’ in Crystals. The polymeric fibres considered were collagen, silk and cellulose, and perhaps in relation to this work, Giulio Fanti felt that WAXS could also be used to study the Shroud. The two papers mentioned at the top of this post quickly followed, using the same samples as Fanti had used before, with the exception of the anomalous Egyptian sample, K.
The X-ray diffraction pattern achieved by firing X-rays at a fibre or collection of fibres is roughly circular, but with distinctive intensity variations transversely across the collection, giving two clear axes of symmetry.
The intensity profiles of the “equatorial” radius of these diffraction patterns were used to distinguish between the fibres, and to give indications of the possible ages. The sharper the peaks, the more crystalline the material, and thus the less deteriorated, and the younger the fabric. Four such profiles are illustrated in the papers.
The three labelled features (D, m and M) were quantified and combined to produce an ‘Ageing Factor,’ which could then be plotted against the known age of the samples to produce a calibration graph. Here are the ‘Aging Factors’:
And here is a graph of these results. The black trend lines and red ‘Shroud’ lines are mine, and will be explored below:
Well, what are we to make of this? Firstly we note that the samples are the same as those of Giulio Fanti’s papers, with the exception of the anomalous Egyptian one, and that this time, whole threads were used, not just individual fibres. This may be significant, as it was noted above that about half the fibres from any single thread were considered unrepresentative by Fanti. It is not at all clear whether all the previously rejected but now included fibres were similarly unrepresentative, or if, in the final analysis, the new data means anything at all.
Assuming it does, we can see that the best fit line is a curve suggesting accelerating deterioration with age, until about 2500 years old, after which there is no further damage. This does not compare well with the more or less linear mechanical deterioration to at least 5000 years old observed in Fanti’s earlier papers.
Having published the calibration graph in 2019, the Shroud test followed in 2022, and the Shroud had an Ageing Factor of 10 (Shroud A on the graph), intrinsically suggesting a date of about 200 AD, most similar, according to the authors, to the Masada fabric, which sat in the desert for nearly two thousand years, at an average winter temperature only just below Turin’s average summer. Masada’s average annual temperature is 21°C. Turin’s is 12°C. Assuming, for the sake of argument, that the Shroud is authentic, then it spent only a few years in Jerusalem before moving to Turkey, was in Constantinople for 200 years, France for 200 years, and Italy for 500 years. If temperature is directly related to deterioration, the Shroud should appear much younger than the Masada fabric.
The authors’ counter to that is that humidity is also a significant factor. Deterioration is accelerated not only by increased temperature but also by increased humidity, but, as ambient temperature increases, ambient humidity tends to decrease. They calculate that 700 years of about 12.5°C and a relative humidity of aboiut 75%, coupled to 1300 years of about 22.5°C and a relative humidity of about 55% would generate the Aging Factor of 10.0 that they measured off their sample of Shroud thread. Without the extra 1300 years, the Aging Factor would only be 7.65, almost corresponding to a modern cloth (Shroud C on the graph). To be medieval, under the same environmental conditions as the Masada or Fayyum textiles, the Shroud should have an Ageing Factor of about 8.3 (Shroud B)
Finally, in order to counter any suggestion that the 1532 fire of Chambéry would have accelerated the deterioration of the cloth, a sample of linen fabric was heated to 200°C for thirty minutes, an approximate simulation of the fire. The fabric became very discoloured, but the Aging Factor of the heated cloth was no different to that of an unheated cloth, which the authors attribute to an exact cancelling out of the heat/humidity factors.
Q.E.D.? Sadly not. Although the authors declare no conflict of interest, which may in its commonly recognised financial sense be true, at least two are deeply personally convinced of the authenticity of the Shroud, and three were authors of a Plos One paper on the characterisation of the blood on the Shroud which was subsequently retracted by Plos One, which decided on reconsideration after “concerns have been raised” that “the main conclusions of the article are not sufficiently supported,” specifically that the extrapolation of results from a single fibre of insecure provenance to describe the degree of suffering of a tortured man were unjustifed (Carlino, Elvio; De Caro, Liberato; Giannini, Cinzia; Fanti Giulio, ‘Atomic resolution studies detect new biologic evidences on the Turin Shroud,’ Plos One, June 2017). Significantly, WAXS was involved in that investigation too. Furthermore, Giulio Fanti is convinced the Shroud is authentic based on a personal revelation in 1998 (see shroud.com/pdfs/Fanti-refl.pdf), and De Caro has published several papers justifying the visions of Maria Valtorta, whose “Poem of the Man God” was published in 1956 (e.g., Matricciani, Emilio and De Caro, Liberato, ‘A Mathematical Analysis of Maria Valtorta’s Mystical Writings,’ Religions, November 2018, and De Caro, Liberato, et al., ‘Hidden and coherent chronology of Jesus’ life in the literary work of Maria Valtorta,’ SCIREA Journal of Sociology, December 2021). The claim that the authors have no conflict of interest, when they are actually avowedly committed to the authenticity of the Shroud, is dishonest, even if their experimentation was flawlessly unbiased, which I’m sure it was.
Mechanically, there is no doubt that the Shroud, which has been folded, rolled, hung and repacked in many different ways would be expected to be considerably weaker than an equivalent cloth left in a cupboard – or tomb. If it is two thousand years old it ought to have the breaking strain of a much older fabric, and if it is seven hundred years old it might appear, perhaps, to be from about 600 AD, as indeed Fanti’s paper found it to be. Whether the same can be said for the crystal structure of the cellulose is difficult to say. As it moved from Lirey to Chambery, via being carried around France by Margaret de Charney, and then finally to Turin, we have no idea what temperatures and humidities it might have been subject to.
But there’s more. Fanti claims that this Shroud sample is “a thread taken in proximity of the 1988/ radiocarbon area (corner of the TS corresponding to the feet area of the frontal image) near the so-called Raes sample.” When this thread was taken and who took it is not mentioned. Was it, in fact extracted from the Raes sample? Why not say so? Or was it extracted, by Luigi Gonella, from the Riserva portion of the strip cut off by Riggi di Numana in 1988? In his paper for Thermochimica Acta, Ray Rogers writes: “I received samples of both warp and weft threads that Prof. Luigi Gonella had taken from the radiocarbon sample before it was distributed for dating. Gonella reported that he excised the threads from the center of the radiocarbon sample,” and the provenance of these was thoroughly investigated by Thibault Heimburger. Did Fanti get his sample from Gonella? Why not say so?
Here are photos of the thread under examination:
The little tuft not clamped was the X-rayed area. A series of eight X-rays was taken, at 0.1mm intervals along the arrow marked X, and combined to give the measurements discussed above.
To mainstream sindonologists (mostly American) this will present a challenge. One school of thought is that the Shroud in that area is so covered in grime and contamination that any kind of experimentation with it is bound to be fruitless. Another claims that this area was substantially repaired during the Middle Ages and that threads from this region are either medieval cotton or closely interwoven with medieval cotton, and a third claims that the miracle of the Resurrection flooded the area with neutrons, which must surely have had some deleterious effect on the cellulose. Actually discovering that this piece of Shroud might be accurately dateable will disturb some of these ideas.
Ignoring the Shroud for a moment, it might be thought that the possibility of dating archaeological textiles by two or three different methods could only be a good thing. If mechanical deterioration could really be used as a chronograph, then surely it would have been taken up by now, but a glance at Google Scholar tells us that ‘Multi-parametric micro-mechanical dating of single fibers coming from ancient flax textiles’ has only been cited 11 times since publication in 2014, 7 times by Fanti himself, and all of them solely in connection with the Shroud. The archaeological world, it seems, remains unimpressed. We’ll have to wait to see if this crystallographic idea meets with better success.