I am a relief (aka substitute, supply) high school teacher and today I had several Society and Environment (i.e. Social Studies) classes.
One of the lessons in one of those S&E classes that I taught today was about how archaeologists date the past.
[Left (click to enlarge): Easton, M., et al., "SOSE Alive 1: Studies of Society and Environment," John Wiley and Sons: Milton QLD, Australia, 2003, p.15]
There was nothing surprising about that. But it was surprising that the example of radiocarbon dating cited was that of the Shroud of Turin. And what was astonishing (to me at least) was that the textbook actually debunked the 1988 radiocarbon dating of the Shroud, by pointing out that after that radiocarbon dating which "indicated the cloth was only around 700 years old," "further tests were done" and "These proved that only the bacteria and mould on the cloth were around 700 years old," and so "The mystery continues":
"One famous object that has been radiocarbon dated is the Shroud of Turin - said by some to be the cloth in which Christ was wrapped after his crucifixion. These tests, carried out in the late 1980s, indicated the cloth was only around 700 years old. Then further tests were done. These proved that only the bacteria and mould on the cloth were around 700 years old. The mystery continues. Written records confirm the cloth did exist in 1357." (Easton, M., et al., "SOSE Alive 1: Studies of Society and Environment," John Wiley and Sons: Milton QLD, 2003, p.15).
Unfortunately there was no time to discuss the dating of the Shroud in class, but many of the students in that class (and innumerable students across Australia since the book was first published in 2002) would have read that paragraph and would have absorbed its take-home message that the radiocarbon dating of the Shroud of Turin as being only 700 years old, was flawed.
Now I don't totally agree that the reason the Shroud was carbon-dated to around 1325 AD was because the bacteria and mould on the cloth was 700 years old. But I do agree that the bacteria and mould on the Shroud, being more recent carbon, would have markedly skewed the radiocarbon age of the Shroud to make it appear to be younger than its actual chronological age.
And what's more, the late Prof. Harry Gove, co-founder of the AMS radiocarbon method used to date the Shroud also agreed, that the "bioplastic coating of the linen fibrils could not have been removed even by the most stringent pretreatment cleaning process and would, definitely, skew the real age of the linen":
"The C-14) test performed at the Arizona AMS clearly showed a wide discrepancy, on the average of 550) years between the linen and the bird's body. Microscope examination showed the presence of a bioplastic coating not only on the bird's and mummy's wrappings, but also on the Shroud, a sample of which Dr. Garza-Valdes studied in Turin. In his own words, `As soon as I looked at a segment in the microscope, I knew it was heavily contaminated. I knew that what had been radiocarbon dated was a mixture of linen and bacteria and bioplastic coating that had grown or. the fibers for centuries.' [Barrett, J., "Science & the shroud," The Mission, Magazine of The University of Texas Health Science Center at San Antonio, Spring 1996]. Naturally, Dr. Garza-Valdes' discovery, was received with skepticism by some scientists ... However, on December 22, 1998, in a TV interview aired by the learning channel on cable TV, Professor Harry Gove, the co-inventor of the AMS procedure stated unequivocally that, `... bioplastic coating of the linen fibrils could not have been removed even by the most stringent pretreatment cleaning process and would, definitely, skew the real age of the linen.'[TLC-TV: In Pursuit of the Shroud, Dec. 22, 1998.]" (Konikiewicz, L.W., "Turin Shroud and the Science: Digital Enhancement Provides New Evidence," Panorama Publishing:, Chicago IL, 1999, pp.44-45).
What is really important about this paragraph in a high school textbook is that it is evidence that it is becoming increasingly widely accepted in the broader scientific and academic world generally that the 1988 radiocarbon-dating of the Shroud as "medieval" was wrong!And to paraphrase Harvard geneticist, Prof. Richard Lewontin:
"... to put a correct view ... into people's heads we must first get an incorrect view out."