As of 2005 peer-reviewed science published in Thermochimica Acta and confirmed by two other independent, and different approaches, also published and peer-reviewed, the 1988 Carbon14 tests have been invalidated. What they tested has been proved to be non-homogonous with the main body of the shroud.
The Shroud of Turin is made of pure 100% Flax originated Linen. The sample cut from the corner of the Shroud, has been shown beyond doubt to contain DYED EUROPEAN COTTON interwoven into original Shroud Linen material in an approximate 60% cotton to 40% original linen to 40% to 60% linen mix along a diagonal area across the sample. Microscopic examination shows a clear interweaving of the two different threads. The cotton threads have been dyed with a alum containing mordant dye to match the color of the aged linen and then butt end to butt end re-twist spliced into the original linen threads... then the weave re-done to match the original weave pattern using the newly added threads in both the woof and warp directions until the material becomes 100% cotton all the way to the edge of the shroud as an invisible repair. This technique, developed in the 14th Century is known as French invisible reweaving and is done only by very skillful artisans to repair very valuable cloths and there are practitioners even today.
The patch cotton material is dyed, fullered, bleached and spun differently than the material the rest of the Shroud composed of. The Shroud body itself contains absolutely no cotton. The patch contains 2% aluminum bound in the alum in the mordant used to fix the Madder Root dye... the main body of the Shroud has less than .002% aluminum... consistent with environmental soil exposure. The patch area contains significant amount of vanillin while the Shroud body itself, and the shroud threads in the patch no vanillin at all.
An examination of the surviving sub-sample C of the five sub-samples cut from the sample taken for the 1988 C14 tests clearly shows, under microscopic examination, the change from linen on the shroud side to cotton on the patch side. One of the labs in the 1988 test reported the anomalous cotton in the sample they received and it is footnoted in the Nature report on the test but ignored.
Finally, another scientist working with threads taken from the sample had one separate spontaneously at the splice... one side was cotton... the other linen. He was able to identify the species of cotton as a European form grown in France.
Chemical and physical and biological testing have conclusively proved that the sample that underwent C14 testing is NOT THE SAME MATERIAL as the material that makes up the main portion of the Shroud of Turin. It is a melange, a mixture, of older original shroud cloth and newer patch material.
Statistical specialists started questioning the results when it was learned that both the Arizona lab, who did EIGHT tests on their two samples (from the two extreme ends of the main sample) and got datings that were too far out to have come from a homogenous sample, so decided to average their results to get them closer for their report... and then Oxford who did the SAME THING to the overall data to also cover up datings from all three labs that were too far apart to have come from a homogenous sample. The Chi Squared tests were way too far off... and peer-reviewed papers appearing after the tests challenged the results. One stated categorically that looking at the raw data from the tests, that the data could NOT have come from a homogenous sample.
Ergo, the sample tested in 1988 is irrelevant as the age of the main body of the Shroud. They did not test the shroud. They tested a patch of unknown provenance... because they broke the sampling protocols.
However, Harry Gove, the inventor of the technique used by all three labs in the 1988 test, when asked how old the original material would have to be that, when mixed with the 16th century patch material in the observed percentages, would give the 1988 test result dates, did some quick calculations... and said "First Century, give or take 100 years."
Great work. Well done!