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Cloth dating   versione testuale

On april, 21st 1988 three portions of tissue were taken from a corner of the Shroud to perform radiocarbon dating. On october, 13th on a crowded press conference Cardinal Anastasio Ballestrero, Archbishop of Turin and Papal Custodian of the Holy Shroud at the time, announced the results of the three research centers charged to perform the analysis (Oxford, Zurich and Tucson). They date the Shroud from 1260 to 1390 d.C.
In the following years heated controversy and an articulate debate aroused among the experts about the dating process accuracy and results, its incompatibility with the results produced in other research fields and, particularly, about radiocarbon dating reliability to date an object with so distinctive historical and chemical-physical characteristics as the Shroud is.
The whole dating process leads to many perplexities and lays itself open to critics by those who believe it was managed superficially and not consonant with the object’s importance and peculiarity.
First of all, the behaviour of Dr. Tite of the British Museum, standing guarantor of the whole process, and of those in charge of the three research centers, was a surprise since they precluded any other analysis and researcher categorically refusing to make carbon dating process part of a multidiscipline context of analysis and exams to be carried out contemporaneously, even if this was suggested by many.
The sample was taken, making an extemporaneous choice, from a single point which is one of the most polluted of the cloth and, therefore, one of the less suitable to be correctly dated. Those who took the sample – afterwards divided into parts to be given to the three research centers – gave conflicting versions about the samples weight and measures. Moreover, according to the official data, the sample’s weight was nearly doubled compared to how much it should and according to the Shroud uniform weight by square centimetre precisely calculated by the 1978 tests. Why? There are two possibilities: either the data were wrong or they did not refer to the Shroud sample.
But doubts and incongruities do not end here. For months the three centers have asked for a test to be carried out «blindly» (by dating, contemporaneously to the Shroud sample, other two samples previously put into anonymous holders to prevent the identification of the one with the Shroud sample) to guarantee total impartiality. Yet, they always knew the tissue, owing to its very special weave, is highly recognizable and, what’s more, analysts wanted to personally witness the sampling also because they did not trust in the ecclesiastical authority honesty. Moreover, the function of the check samples has been totally thwarted by the official communication of their age to the three centers just before the dating process. Finally, the results given by each center are considerably contradictory and this issue was not discussed about due to the centers persons in charge refusal to give the «primary data», that is to say the not yet interpreted and compared data.
There are many more perplexities but we believe the listed ones are enough to say the whole operation has not scientifical certainty.
It is furthermore necessary to stress that an organic sample carbon dating has intrinsic and precise limits. These are due mainly to a measure uncertainty that depends on the sample carbon quantity and on the used count method. Moreover, it is very difficult to ascertain the sample «isotope integrity», that is to say if some more C14 quantity was added to the one present when the organism died (in this case, when the linen used to spin the Shroud was collected). This is highly probable if one considers the turbulent history of the Shroud. Actually, it is important not to forget that polllens, spores and filaments were found on the Shroud, that during the Chambéry fire the tissue was subjected to a sufficient temperature to fuse a silver shrine’s corner and was imbued with the water used to stop the fire, it was exposed for long periods both outside and indoors saturated by the candles’ smoke and it was subjected to many other ups and downs (a XVIth century chronicler tells that it was even put in boiling oil).
It is therefore important to value the C14 dating reliability processed on such a special find as the Shroud is, taking into account scientific literature is full of resounding episodes of dating mistakes caused by contaminations and other unpredictable elements. Moreover, the carbon dating method is not the only existing dating method and, therefore, a serious analysis can not prescind from a comparative examination of the reliability and precision of all the dating methods known today (infrared luminescence, cellulose depolymerization etc...).
It may be a paradox, but to have one more element (the presumed medieval dating of the tissue) does not help in solving the Shroud mistery that, on the contrary, is thickened even more. Actually, the determination of the tissue age is a kind of research that must be compared to the many interdisciplinary studies made in this century and especially after the tests processed by qualified teamworks formed by italian and foreigner experts between october, 9th and 13 th 1978.
All these researches agree on describing the Shroud a «nonreproducible» object with unique chemical and physical characteristics. The possibility that it is an artefact is therefore precluded: the image was certainly left by a tortured and scourged man who was lastly crucified.
The result is that the only hypothesis that can make coexist the above-mentioned results and the tissue medieval dating (considering that crucifixion had fallen into disuse many centuries before the medieval period) is the one of an image made by a medieval «copyist» who, taking inspiration from the Gospels to the letter, tortured and crucified a contemporary by methods and characteristics (like, for example, the nails plunged into the wrists instead of the hands’ palms) alien to his time’s culture, just to build a false Jesus Christ burial cloth. So, he succeeded in creating a perfect and unique image that XXth century experts have not yet reproduced despite the many experiments, the acquired knowledge and tools. An image rich in details confirming its authenticity (pollens, coin, etc.) invisible to the eye and that only the most modern analysis tools could detect. The above-mentioned hypothesis is therefore not much plausible to say the least.
All the Shroud research groups worldwide were involved in the C-14 debate at many international meetings. Recent experimental studies (by Leoncio A. Garza-Valdes in San Antonio (Texas) and by Dmitrij A. Kouznetsov and Andrej Ivanov in Moscow) have furthermore opened the sientific debate about the tissue dating once again, with results seeming to prove a possible and considerable chemical and biological contamination of the tissue and therefore making it fundamental to start a wider research program to study and value the problem of introduction of a correction factor to the radio carbon date. During the International Symposium “The Turin Shroud: past, present and future”, held in Turin in 2000, scientists discussed a lot about many aspects and valuations of the radio-carbon dating results hoping for different new research opportunities.
We can therefore conclude that the problem of the tissue dating is still to be solved since, due to possible chemical and biological contaminations along the centuries (to be verified and valued quantitatively by repeated analysis), the 1988 “radio carbon” date may be remarkably different from the real one.