A piece of linen cloth, 4.34 m long and 1.09 m wide, kept in the cathedral at Turin (Italy), has been claimed as the burial shroud of the Jewish prophet Jesus of Nazareth, in whose name the Christian religion was founded. It is thus venerated as a ‘relic’: an object with special properties of sanctity derived from its (alleged) connection with someone considered especially holy. In the case of an object supposedly associated with the death and resurrection of a person claimed by adherents of the Christian superstition to be a third part of their god, this makes it about as holy as anything could possibly be.

The shroud has been claimed as “the most intensely studied artefact in human history”, which may be a bit of an exaggeration, but which is probably not far from the truth. The modern interest in it, which began this intense scrutiny of evidence for its authenticity, began in 1898, when Secondo Pia, a Turinese lawyer and keen photographer obtained permission to photograph the cloth during its exposition that year. As he developed his plate, he became aware of a curious phenomenon: the indistinct, yellowish markings on the cloth now appeared more definite and, curiously, the negative plate more closely resembled a positive portrait photograph than a negative. To Pia, this was clear proof that the cloth could not have been a forgery, for what forger could have anticipated the invention of photography and created a negative? Pia’s discovery seemed to confirm a miraculous origin for the image on the cloth and there the matter rested for many years, the credulous and faithful seeing it as a genuine relic of the resurrection of Jesus, the sceptical regarding it as a skilful medieval forgery.

Following the publication of a post at the Shroud of Turin Blog, accusing us of doing Bad Archaeology, I’ve updated this page. To avoid being further accused of altering things to deflect criticism, I’ve struck through the errors in the original and added corrections where appropriate. The fact that I’ve had to do this in only two places is a measure of how devastating a critique of this page it has presented!

Scientific studies

Two scientific studies of the cloth were made in the 1970s, one in 1973 and one in 1978; the second is the better known, thanks to a concerted campaign by members of the team to publicise what they saw as clear proof of the shroud’s authenticity, whereas the earlier report was published only in Italian. The 1973 study was the outcome of a commission set up in 1969 by Cardinal Pellegrino to examine the cloth’s condition, take new photographs and to make recommendations on its conservation. The results were announced by the Centro Internazionale di Sindonologia (International Centre of Sindonology) in Turin, an organisation that upholds its origin in the first century CE.

The best known result of these tests was the report on pollen by Max Frei, who claimed to have identified pollen spores that could only have come from Palestine. On the other had, Gilbert Raes’s analysis of the textile concluded that its twill (three-to-one herringbone) weave was common at many different periods but not in Palestine or Egypt in the first century CE, where tabby (plain) weave was usual, as seen on Egyptian mummy cloths and the wrappings of some of the Dead Sea scrolls. A few cotton fibres were also present: cotton was first imported into Europe during the twelfth century CE but was used in the Near East during the time of Jesus, so their presence was inconclusive. One suggestion, made by Silvio Curto, a collector of Egyptian cloth, was that the shroud might be authentic or might be no earlier than the tenth century CE.

STURP

If the 1969-73 Commission was cautious in its conclusions, the 1978 Shroud of Turin Research Project, Inc. (STURP) was never able to make a formal, conclusive report, perhaps in part because it was caught up in political and religious intrigues. Members of the team were forced to sign an oath of secrecy, preventing them from publishing results before the report was due to be published in 1980. By that time, there was no sign of a report and individual team members had published their results elsewhere. And those results were controversial: team members disagreed with each other over the significance and meaning of what they had found in a war of words that was conducted in public.

One of the team, Walter McCrone, resigned in 1980, claiming that threats had been made on his life for his sceptical suggestions that the shroud was a medieval forgery. Two members, Kenneth Stevenson and Gary Habermas (the latter a professor at fundamentalist Jerry Falwell’s Liberty College), stated that the odds of the image not being Jesus of Nazareth were “one chance in 82,944,000”. Whilst fundamentalists are inordinately fond of quoting probability statistics about the unlikelihood of something happening by chance, they rarely reveal the basis on which their calculations are made, and this is no exception. It is such a precise figure that it instantly raises suspicion. It was claimed that traces of iron oxide in the ‘blood stains’ showed that these red marks were real blood: one tester, Baiama Bollone, claimed to have identified its type as AB, which he claimed matched miraculously transformed wine in the Eucharistic Miracle of Lanciano, confirming that this was indeed the blood of Jesus. Others were more worried about the colour, as dried blood is brown, not red.

Nevertheless, the overwhelming public impression after the STURP study of 1978 was that the authenticity of the shroud had been demonstrated beyond all reasonable doubt. Still, there remained disquiet among many that radiocarbon dating had not been attempted and that the scholars chosen to run the tests were from christian religious denominations with a vested interest in the cloth. During the 1980s, negotiations to submit samples of cloth to Accelerator Mass Spectrometry dating, which requires much smaller samples than older techniques. In 1987, agreement was reached to test seven samples weighing no more than 50 g and tested independently in seven separate laboratories that would not be allowed to share their results.

In the event, three laboratories were chosen (Arizona, Oxford and Zürich) and asked to perform several tests on each of four samples taken from different parts one corner of the cloth, that had been carefully checked to be free from later repairs. The sample dates (in years before present (bp) with likely error) from each laboratory were as follows:

Sample 1: Arizona (AA-3367): 591±30 bp, 690±35 bp, 606±41 bp and 701±33 bp.
Sample 1: Oxford (Ox-2575): 795±65 bp, 730±45 bp and 745±55 bp.
Sample 1: Zürich (ETH-2883): 733±61 bp, 722±56 bp, 635±57 bp, 639±45 bp and 679±51 bp

Sample 2: Arizona (AA-3368): 922±48 bp, 986±56 bp, 829±50 bp, 996±38 bp and 894±37 bp
Sample 2: Oxford (Ox-2574): 980±55 bp, 915±55 bp and 925±45 bp
Sample 2: Zürich (ETH-3884): 890±59 bp, 1,036±63 bp, 923±47 bp, 980±50 bp and 904±46 bp

Sample 3: Arizona (AA-3369): 1,838±47 bp, 2,041±43 bp, 1,960±55 bp, 1,983±37 bp and 2,137±46 bp
Sample 3: Oxford (Ox-2576): 1,955±70 bp, 1,975±55 bp and 1,990±50 bp
Sample 3: Zürich (ETH-3885): 1,984±50 bp, 1,886±48 bp and 1,954±50 bp

Sample 4: Arizona (AA-3370): 724±42 bp, 778±88 bp, 764±45 bp, 602±38 bp and 825±44 bp
Sample 4: Oxford (Ox-2589): 785±50 bp, 710±40 bp and 790±45 bp
Sample 4: Zürich (ETH-3882): 739±63 bp, 676±60 bp, 760±66 bp, 646±49 bp and 660±46 bp

This is an unprecedented number of samples, one set from the shroud and three control samples: the laboratories were not told which sample came from the shroud and which from the control objects. Those from each sample are consistent, so they can be combined into means. Sample 1 therefore has a mean radiocarbon date of 691±31 bp, which calibrates to 1262-1312, 1353-1384 CE at 2σ (95% confidence); sample 2 has a mean of 937±16, which calibrates to 1026-1160 CE at 2σ; sample 3 has a mean of 1,964±20, with a calibration of 9 BCE – 78 CE at 2σ; and sample 4 has a mean of 724±20, with a calibrated range of 1263-1283 CE at 2σ.

What do these dates mean? Sample 1 was from the shroud, sample 2 from linen from a Nubian tomb of the eleventh to twelfth centuries CE, sample 3 was linen from a mummy of the early second century CE and sample 4 was from threads removed from the cope of St Louis d’Anjou dated to 1290-1310 CE. There is therefore no question that the shroud is not medieval; we can be 95% confident that the cloth was manufactured between 1262 and 1384 CE. The chances of it dating from the first century CE are so vanishingly small that they can be discounted completely. This did not surprise those who had always believed the shroud to be a medieval fake, as documents relating to its first known exposition c 1357 describe it as having been made ‘recently’: the date fits well with the radiocarbon assay. There can then be little doubt that the image it bears was painted on the cloth.

Update 2009

In 2009, it was reported that a genuinely first-century CE burial shroud has been discovered in the Hinnom valley in Jerusalem. This is the first discovery of its kind and provides the first material with which to compare the Turin Shroud. This shround was found in a tomb that had been partly disturbed by looters, which is why Professoir Shimon Gibson from the Israel Antiquities Authority excavated it completely. As usual, the looters were looking for saleable artefacts, such as ossuaries, and left the shroud as valueless.

The survival of the cloth is unusual and seems to have occurred because, unusually, the tomb was completely sealed with plaster, which had prevented the tomb from becoming damp. Furthermore, the relatives of the man buried in the shroud had not returned to gather up the for deposition in an ossuary. The reason for this appears to have been that the deceased had suffered from leprosy and tuberculosis, which were detected in DNA samples taken from the surviving bones.

So how do the charateristics of this certainly first century CE cloth compare with those of the Turin Shroud? Firstly, the “Hinnom Shroud”, as it may be called, is not a single piece of cloth. Rather, it consists of a mixture of woollen and linen cloths, stitched together into a patchwork, unlike the single piece of linen that comprises the Turin Shroud. There is also a separate piece of cloth to cover the face, which is what would be expected from what we know of Jewish burial customs of the period. Secondly, whereas the weave of the Turin Shroud is a type known as twill, a weave with a characteristic diamond pattern (denim is a cloth with twill weave), that of the “Hinnom Shroud” is a simple cross-weave. Twill was unknown in the Middle East until the medieval period, which has long been seen as a problem for the Turin Shroud’s authenticity as the burial cloth of a Jew of the first century CE. Now we have an undisputed shroud from the right time and place, it does not have a twill weave. Moreover, it conforms more to what we would expect from a Jewish burial cloth rather than to something a medieval artist might imagine one to have been.

The “Hinnom Shroud” consists of a patchwork of cloths with a separate piece for the head, all made in a plain two-way weave, quite unlike the Turin Shroud. Going back to the Gospels – our only sources of information about the burial of Jesus – we find that they mention not a single cloth but “strips of linen” (Luke XXIV.12 and John XX.5, both using the Greek word ὀθόνια, meaning ‘small pieces or strips of linen’). Supporters of the authenticity of the Turin Shroud are careful not to quote these passages, which show that the evangelists did not think of the body of Jesus as ever having been wrapped in a single linen cloth.

However, it has not been an entirely sceptical year for sindonology. Earlier in the year, a researcher in the Vatican archives, Dr Barbara Frale, announced that she had discovered faint writing on the shroud, while studying digitally enhanced photographs produced in 1994. In her book La Sindone di Gesu Nazareno, she goes further than the STURP team, which believed that it had identified several letters close to the head of the image, and counts eleven words in total in the same area. Some words are in Greek, others in Aramaic, yet others in Latin. She claims that among other things, there is the Greek phrase [Ι]ησου[ς] Ναζαρηννος ([I]esou[s] Nazarennos, ‘Jesus the Nazarene’) as well as a fragment reading …ιβερ… (…iber…), which she interprets as part of the name of the Emperor Tiberius (42 BCE – 37 CE). Describing the ‘text’ as a ‘death certificate’ glued around the head of the deceased, she interprets it as reading “In the year 16 of the reign of the Emperor Tiberius, Jesus the Nazarene, taken down at the ninth hour, after having been condemned to death by a Roman judge because he was found guilty (of inciting the people to revolt) by a Hebrew authority, is hereby sent for burial with the obligation of being consigned to his family only after one full year. Signed by…” (the name of the signatory cannot be read).

Barbara Frale is an expert on medieval documents: she was responsible for the publication of the Vatican’s archives relating to the suppression of the Knights Templar early in the fourteenth century and has claimed that the order once owned the Turin Shroud. However, her work has not been well received, except by true believers. Some have suggested that the letters are imprinted from a reliquary laid next to the shroud in the medieval period, which she dismisses. She claims that a medieval text could not refer to Jesus as “the Nazarene”, as this would have been “heretical”. It is also highly unlikely that the three languages she claims to read would be mixed in an offical ‘death certificate’; although both Aramaic and Greek are found on ossuaries of the period, Latin is completely absent and was not used in official documents in the region. The ecclesiastical historian Antonio Lombatti has suggested that Frale’s ‘letters’ are just a product of pareidolia, the innate human tendency to make meaningful patterns from random splodges and dots. This makes a lot of sense. The ‘words’ have to be teased out from three quite different languages, never mixed in other contexts, in much the same way as ‘EVP (electronic voice phenomena, claimed to be voices of the dead) manifest as utterances in numerous different languages, each word an example of apophenia.

A mess from television

On 30 December 2009, Channel 4 (UK) showed a documentary claiming to present “new evidence” that the Turin Shroud is not a medieval fake. They wheeled out members of the 1970s STURP team, the 2005 paper published in Thermochimica Acta claiming that the radiocarbon dates were contaminated by cotton of sixteenth-century date and ended up presenting nothing that’s not already known.

It was in the documentary’s omissions that the greatest faults lay. The voice-over stated that the image is not painted, giving the impression that nobody could explain the colouring other than that it’s a “degradation of the cellulose” in the linen fibres. That’s not quite correct. What is seen on the shroud is a chemical darkening of a starch and polysaccharide coating on some of the fibres: it’s not the fibres themselves, but something applied to them after manufacture. In other words, pigment. And if that’s not paint, I really don’t know what is. One of the members of the STURP team, Walter McCrone, concluded during the study that the image was painted using red ochre and vermillion pigments. The programme didn’t mention him or his conclusions!

The documentary also stated that the blood stains seen on the shroud must be real blood, as they contain degradation products from haemoglobin. Even if this be accepted – and there is still the problem that these stains are red, not brown like real dried blood – it does not mean that the blood derives from a corpse wrapped in the shroud. Given that the image was introduced as a coating on the fibres, it is equally likely that the “blood” was introduced in the same way. Why couldn’t a medieval forger have painted on blood using, say, cow’s blood, which would have been readily available (even though McCrone thought it to be vermillion)?

The scientists at the radiocarbon laboratories noted contamination of the samples with cotton, while McCrone had already drawn attention to the mixture of cotton and linen. This means that they were able to deal with it. They recognised the cotton and removed it, dating the linen fibres, which is what they were asked to do. The preparation of samples for dating involves rigorous cleaning to remove potential contaminants, such as these stray cotton fibres. There is no reason to suspect that the three laboratories undertaking the dating did not do their basic cleaning, especially as they had spotted the contaminants.

The Shroud of Turin Blog says that “[c]otton isn’t the contaminant here. It suggests the possibility of other contaminants’, which is a bit of a red herring. Cotton was blamed by the programme for potentially contaminating the sample and as evidence that the piece removed for testing was part of a repair. The Shroud of Turin Blog’s author has made the a priori assumption that there must be contamination of the sample because he doesn’t want to accept the date provided by the laboratories. Bringing up “[m]adder root dye, aluminum products [and] gum’ is not an answer. Ray Rogers found these materials (one of which is a pigment, incidentally, something that the Shroud of Turin Blog denies is present on the Shroud!) in two thread samples that were said to have been left over from those submitted for radiocarbon dating whist claiming that they are not present on the rest of the Shroud. They are. The question of the vanillin content is also relevant here: Ray Rogers has used the lack of vanillin in the lignin of the main cloth fibres to estimate the date of the Shroud as between 3000 BCE and 700 CE, which is a very wide range of dates, but significantly older than a fourteenth-century cloth. The problem here is understanding the rate of loss of vanillin from the linen fibres, especially considering the effects of the fire that damaged the cloth in 1532. It is unclear how much vanillin is supposed to be present in the fibres examined by Rogers.

The programme brought up the old claim that the image on the shroud somehow encodes three-dimensional data and, using the same computer program used to create a three-dimensional image of the face on the shroud, showed that it does not work with photographs. How dishonest! We’re not dealing with a photograph on the shroud but with a painted image. The comparison should have been with a painting. Talk about prejudged conclusions! Besides, if we’re dealing with an image produced by draping a cloth over a corpse, it ought to be far more three-dimensional than we see: where are the sides of the body that the cloth would have touched? The fact that they aren’t there is good evidence that the image is painted a result of the application of a pigment, detected chemically.

The Shroud of Turin Blog objects to my quoting the television programme’s testing photographs to derive three-dimensional data from the Shroud. The blogger has advised me to have a look at a site that tries to explain the alleged three dimensional encoding in the image. According to its author, the Shroud image does not have the type of shading that is found in photographs or paintings: “[t]here is no direction to what seems like light. Something else is causing the lighter and darker shades. That is looks like light to us is an optical illusion” (spelling error in the original). Now, I’m no graphic artist, but even with limited photographic manipulation skills, I’ve been able to come up with the image on the right. Firstly, I plotted a well known monochrome photograph as a bump map; then I rendered it in negative; next, I applied a bit of perspective; finally, I turned it green (as it’s generally a green image of the face on the Shroud that is shown in an allegedly three-dimensional form). The results aren’t exactly spectacular, but they are approaching the nature of the picture derived from the Shroud. What I find expecially interesting is the way that unevenness in the surface of the scanned photograph show up beautifully as three-dimensional. So, I have conducted my own brief experiment (I spent two minutes playing with the image) and found that this alleged property of the Shroud is not as unique as is claimed.

The Shroud of Turin Blog asks “[d]id you mention that the coating is 200 to 600 nanometers thin?”. Walter McCrone’s 1998 explanation, that it’s a result of a very dilute vermillion and red ochre tempera, sounds reasonable and would explain the thinness. McCrone examined samples from the Shroud and identified the chemicals used. He also pointed out that the technique, known as grisaille, was common in the fourteenth century. I suspect that the thinness of the coating – and it’s significant that the blog claiming to detect Bad Archaeology here admits that it is a coating – is a result of the extreme dilution noted by McCrone (0.01% in a 0.01% gelatin solution: remember, these are the results of tests, not wishful thinking). The fact that Ray Rogers, whom The Shroud of Turin Blog quotes with evident approval, was unable to find any evidence for pigments using visible and ultraviolet spectrometry, infrared spectrometry, x-ray fluorescence spectrometry, thermography, pyrolysis-mass-spectrometry, laser­ microprobe Raman analyses and microchemical testing are effectively meaningless. Two pigments known to have been used in medieval painting, with a carrying medium also known to have been used, were found in one of the tests. That needs to be explained, not glossed over.

Finally, there was no mention of the contemporary Bishop of Lirey’s enquiries into the origins of the shroud when it was fist exhibited c1357. He identified the artist responsible for its creation and there the matter ought to have rested. The technique of tempera painting onto cloth is fourteenth century, the first record of the shroud is fourteenth century and the radiocarbon dates show that it was manufactured in the fourteenth century.

Conclusions

The result is that those who believe the cloth to be the burial shroud of Jesus of Nazareth have tried to dismiss the results of the radiocarbon dating. All manner of bizarre suggestions have been made, from irradiation during the miracle of Jesus’s resurrection to contamination by fungal spores of recent date. None of these excuses works. The shroud is medieval and those who believe otherwise are deluded.

As the Shroud of Turin Blog says, “[g]ood archaeology means considering all the facts, not just those that are convenient”. When those who wish to promote the Shroud as a genuine artefact of first-century CE date, they must explain:

• how the Bishop of Lirey was fooled in 1357 by someone who claimed to have painted the Shroud;
• how the alleged contaminants in the fibres submitted for radiocarbon dating have produced dates that match so well the date of the Bishop’s alleged artist;
• why there are traces of vermillion and madder on the cloth in sufficient concentrations to produce an image using the medieval technique of grisaille;
• how the image on the cloth is anatomically impossible (the neck is too long, the legs are too long, the arms have not flopped to the side – which would have the unfortunate effect of exposing the body’s genitalia);
• how the cloth has not draped itself around the sides of the body but remained miraculously on a single plane for the imprint of the image;
• why the weave of the cloth is one common in the European Middle Ages but not found on the only definite burial cloth of first century CE date to have been identified;
• why the Gospels refer not to a single cloth but to ὀθόνια, ‘small strips of linen’ (Luke XXIV.12 and John XX.5).

These issues need be addressed if the Shroud is to be demonstrated anything other than a medieval fake.