And you may have heard that once upon a time most people thought the world was flat.
No they didn’t. Like script writers writing for the History Channel, they didn’t think at all
about matters on which they were not well informed.

imageJohn Klotz writes:

Last night [=January 18] there was a History Channel subject on ancient relics which briefly stated about the Shroud: While some have attacked the carbon dating "MOST SCIENTISTS"  accept.

I was bit bummed out by the History Channel thing. Not because I believe it but because I believe the reverse is true as to the opinion of most scientists who had studied the Shroud.

I have been fascinated by the story of "La Principessa" that was identified as a da Vinci drawing even though its provenance had been shrouded in mystery and there is no explanation where it had been for several centuries. You can see the analogy.

For some reason I was "inspired" to dig into a book about the La Principessa this morning to sharpen my analogy. La  Principessa had been carbon dated to the 16th century but here’s the caution by the authors about the weight it carried:

"Carbon-14 dating is a chemical examination based on the way natural elements age, and it can be used to test a material or substance that has a biological origin—such as vellum, cloth, or wood. Carbon is breathed in by animals and plants through the carbon dioxide in the atmosphere. Carbon-14, one of three carbon isotopes, is radioactive and subject to decay over a very long period. Its half-life is 5,730 years, which means that in that period, half of the carbon-14 isotopes will have decayed. By measuring the percentage of carbon-14 that remains in a test sample, it is possible to determine its age to within two hundred years.

"The most famous and controversial case of carbon-14 testing involved the Shroud of Turin, the cloth that is alleged to have been the burial shroud of Jesus. In 1988, carbon testing revealed that the age of the cloth was medieval, which means it could not have belonged to Jesus. That might have settled the matter once and for all, but there was so much interest in the Shroud of Turin, and so much passion

"In 2005, Raymond N. Rogers, a highly respected chemist and a fellow of the Los Alamos National Laboratory, revealed in a scientific journal that the entire cloth was much older than the test sample—at least twice as old, and possibly two thousand years old. The explanation: the corner that was tested had been subject to mending and thus contained newer material. Rogers’s discovery did not stop the controversy, and studies of the Shroud of Turin continue."

Whitney, Catherine; Silverman, Peter (2011-12-19). Leonardo’s Lost Princess: One Man’s Quest to Authenticate an Unknown Portrait by Leonardo Da Vinci (pp. 60-61). John Wiley and Sons. Kindle Edition.

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