THE SHROUD OF TURIN
Dating the shroud by its vanillin content
"As unlikely as it seems, the sample used to test the age of
the shroud in 1988 was taken from a rewoven area of the shroud." Ray Rogers.
"This incident just underlines the fact that the Shroud
of Turin will never go away, and believers will try anything, including
arguments masquerading as science, to prove its authenticity." Jay
Ingram, host of Daily Planet of the Canadian Discovery Channel.
"Science has proved the Shroud of Turin a medieval fake, but
defenders of authenticity turn the scientific method on its head by starting
with the desired conclusion and working backward to the evidence—picking and
choosing and reinterpreting as necessary. It is an approach I call 'shroud
science'." Joe Nickell, Senior Research Fellow, CSICOP.
Ray Rogers is a retired chemist, a Fellow at Los Alamos National Laboratory, and a long-time believer
that the shroud is an actual burial cloth of a crucified man which dates from the first century CE.
a well known theory -- believed by many who reject the Carbon-14 dating of
the shroud in 1988 -- that the small
sample of the shroud which was submitted for
testing was not actually a piece of the original
shroud. It was either:
A piece of cloth that had been used to patch a damaged
portion of the shroud, or
A mixture of cloth -- part actual shroud and a part
Rogers said: "As unlikely as it seems, the sample used to
test the age of the shroud in 1988 was taken from a rewoven area of the
shroud. Indeed, the patch was very carefully made. The yarn has the same
twist as the main part of the cloth, and it was stained to match the color."
It is difficult to conceive how scientists, who were given
the task of removing a representative sample from the shroud for testing, could have
removed cloth from a patched section. But that is the belief of some members
of the STURP team -- a group of American scientists who started to study the
shroud in 1978. It would have been an act of extreme carelessness and lack of
attention to detail. Describing the C-14 sample collection, scientist P.E. Damon
indicated that textile experts took care to select a site from which to take the
sample that was some distance from patches and seams.
5 Presumably, the experts' eye sight was not sufficiently
degraded that they were all legally blind.
Rogers believes that the Carbon-14 results measured by three
laboratories in 1988 are thus closer to the date when the shroud was repaired
than to the date when it
In the past, various methods of estimating the age of the shroud
The color of the linen is one potential indicator. Linen
develops a gradually deepening sepia color over time. Unfortunately,
bleaching methods have changed over the centuries, and so no accurate age
measurements could be made.
Flax fibers collect defects over time from radiation in its
environment. Unfortunately, background radiation varies from place to place.
This would be a very subjective measurement.
Carbon-14 radiometric measurements have had an excellent track
record and are the analytical technique of choice.
Rogers developed a new method of dating linen based on its vanillin (a.k.a.
Linen is made from the flax plant. Lignin is a chemical compound present in
the flax. Vanillin is a breakdown product of the
lignin. As linen ages, the vanillin content declines and eventually
becomes undetectable. Thus,
by measuring the amount of vanillin remaining on the cloth, one might be able to estimate
the age of the cloth.
Rogers believes that vanillin is detectable in the sample
taken for radiocarbon testing. Thus, it must date from medieval times. He
believes that vanillin
is also present in the "Holland cloth" used to patch the shroud. But he could
not detect it in material taken from the rest of the shroud. He concludes that the sample submitted
to Carbon-14 testing "cannot be older than about 1290 [CE],
agreeing with the age determined by carbom-14 dating in 1988. However the
shroud itself is actually much older....A determination of the kinetics of
vanillin loss suggests that the shroud is between 1,300 and 3,000 years old"
3 That is, the flax which made up the shroud was harvested between 1000
BCE and 700 CE. He concludes that
the shroud could have been the burial sheet of Yeshua of Nazareth (a.k.a.
Jesus Christ) who was executed about 30 CE ± 3
years by the Roman Army.
There exists a method called pyrolysis mass spectrometry
which Rogers had used recently for other testing of the Shroud of Turin.
2 It has been shown to generate
extremely precise quantitative measurements of carbohydrates, such as vanillin.
Unfortunately, he allegedly chose to use
a qualitative analysis method: He stained a sample of the shroud in his
home laboratory using phloroglucinol–hydrochloric-acid reagent. If a significant
amount of vanillin is present, the reagent changes its color. In spite of the lack of accuracy of the measurement, he
concluded that the shroud could date to the lifetime of Yeshua of Nazareth.
He published a report in the journal Thermochimica Acta a chemistry
peer reviewed journal, on 2005-JAN-20. 4
Skeptical responses to Rogers dating method:
Carbon 14 is the classical method of measuring the age of
carbon-bearing materials. It is based on sound science -- the precise rate at which
Carbon 14 decays to Carbon 16. But before it could be used to date real
materials, it had to be calibrated by using the technique on samples whose
ages were independently known. Rogers has not performed this necessary
calibration on vanillin analysis.
Some criticisms of Roger's work:
According to Jay Ingram, host of the
Daily Planet TV science program on Discovery Channel: "He's got things
completely backwards. He is supposed to be testing the shroud to see how old
it is, not deciding in advance that it is older and then concluding that
vanillin might be a good clock to prove it. This is bad science. The only
way this could be taken seriously would be if Rogers had tested a wide
variety of cloths, [of known ages], decided that dwindling amounts of
vanillin served as a clock, then -- and only then -- tested the shroud."
Ingram also criticized the "Staining is a rough
guide to the presence of vanillin and cannot detect very small amounts."
Malcolm Campbell, a botanist at the University of Toronto
said: "In biological sciences, a scientist would be hard pressed to get
their paper published if they ever attempted to quantify vanillin on the
basis of this staining technique." 1
Joe Nickel, Senior Research Fellow at the Committee for the
Scientific Investigation of Claims of the Paranormal (CSICOP) wrote: "In
fact, the radiocarbon sample...was destroyed by the testing. Rogers (2005)
relied on two little threads allegedly left over from the sampling, together with segments taken from an adjacent area in 1973. He cites
pro-authenticity researchers who guessed that the carbon-14 sample came from
a 'rewoven area' of repair—'As unlikely as it seems,' Rogers admitted to one
news source....Rogers compared the threads with some small samples from elsewhere on the
Shroud, claiming to find differences between the two sets of threads that
'prove' the radiocarbon sample 'was not part of the original cloth' of the Turin
shroud....The reported differences include the presence—allegedly only on the
'radiocarbon sample'—of cotton fibers and a coating of madder root dye in a
binding medium that his tests 'suggest' is gum Arabic. He insists the
sampled area was that of an interwoven medieval repair that was
intentionally colored to match the 'older, sepia-colored cloth'....However, Rogers’ assertions to the contrary, both the cotton and the madder
have been found elsewhere on the shroud. Both were specifically reported by
famed microanalyst Walter McCrone...who was commissioned to examine
samples taken by the Shroud of Turin Research Project (STURP). After McCrone
discovered the image was rendered in tempera paint, STURP held him to a
secrecy agreement, while statements were made to the press that no evidence
of artistry was found. McCrone was then, he says, 'drummed out' of the
One method of accurately dating the shroud would be to assemble
a group of skilled scientists:
Some who are devout believers that the shroud dates to the
first century CE;
Others who are skeptics who consider the shroud to have been
created as a piece of artwork -- either as a fraud or as a religious icon --
in the fourteenth century; and
Others who are genuinely undecided about the age of the shroud.
They develop a consensus on a precise protocol for
sampling the actual shroud. The material would then be submitted to some
world-class Carbon-14 labs for accurate dating.
Alternatively, a dozen or so shrouds of know ages dating from the
first century CE to the present time could have their vanillin levels measured
using a quantitative technique like pyrolysis mass spectrometry. That
would produce a calibration curve. If the data were reproducible, then a
vanillin test could be used on linen to obtain an accurate measure of its age in
parallel with Carbon-14 tests.
One hopes that the Roman Catholic Church will permit additional
testing on the shroud. Still, additional data is unlikely to produce a
consensus. Beliefs on all sides have hardened and are essentially unchangeable.
- Jay Ingram. "Hard to keep a good shroud story down," The
Toronto Star, 2005-FEB-05, Page F5.
- Raymond Rogers, "Pyrolysis/Mass Spectrometry applied to the
Shroud of Turin," (2004) at:
- Rossella Lorenzi, "Face on the Shroud: Turin Shroud Older Than
Thought," Discovery Channel, 2005-FEB-09, at:
- Raymond Rogers, "Studies on the radiocarbon sample from the shroud of
turin [sic]," Tehermochimica Acta, 2005-JAN-20, Pages 189 to 194. Online by
Science Direct, at:
http://www.sciencedirect.com/ Also in PFD format at:
- P.E. Damon, et al. 1989. "Radiocarbon dating of the Shroud of Turin,"
Nature 337 (1989-FEB), Pages 611 to 615.
- Joe Nickell, "Claims of Invalid “Shroud” Radiocarbon Date Cut from Whole
Cloth," Committee for the Scientific Investigation of Claims of the
Copyright © 2005 by Ontario Consultants on
Originally written: 2005-FEB-05
Latest update: 2005-FEB-05
Author: B.A. Robinson