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The Shroud of Turin, Part 2: An Examination of the Cloth


By: Joseph W. Bergeron, M.D.

This article was originally posted on April 8, 2021 at


The Shroud of Turin contains the faint image of a man identical to the biblical descriptions of the crucified Jesus. Interest in the Shroud of Turin intensified when a photograph in 1898 unexpectedly produced an enhanced, photonegative-like image of the man.1 In a previous post, “The Shroud of Turin, Part 1: An Examination of the Man,” we discussed a forensic medical examination of the man pictured on the cloth. In this post, we’ll examine the physical and chemical characteristics of the cloth and consider how the man’s image may have formed.


Examination of the Cloth

The Shroud of Turin measures 437 cm by 111 cm. The cloth is about 0.34 mm thick, with each thread containing 70–120 linen fibers.2 Microscopic examination reveals the man’s image is the result of yellow color found on the top two or three superficial fibers, each fiber ranging 10–15 micrometers in diameter, within the yarns of surface threads.3   

     Aside from blood stains and serum residue, bodily effluents were not found on the cloth.4 The blood stains contain heme, the oxygen-transporting porphyrin found in blood. Yellow-colored fibers forming the image were not found beneath blood or serum, indicating the image formed after the blood adhered to the cloth.5 The image formation did not damage the blood stains, indicating the image was formed by a mild process.6

     Variation in color density on the image corresponds to the number of colored fibers per unit area rather than true color gradation. This is called the “half-tone effect.”7 Conversely, dye, paint, thermal energy, or gaseous reactants would have produced a color gradient. 

     Researchers found that “reflectance spectra, chemical tests, laser-microprobe Raman spectra, pyrolysis mass spectrometry, and X-ray fluorescence all show that the image is not painted with any of the expected, historically-documented pigments.”8 No fluid meniscus or cemented fibers were observed, ruling out the possibility of fluid application having been used to produce the image.9 No paints, dyes, or stains were discovered despite exhaustive testing.

     Any form of radiation energy—thermal, electromagnetic, or particle—would have penetrated the fiber and altered the cellulose structure in order to produce the image. Cellulose was unaffected by the image formation, however.10 

     A fire almost destroyed the Shroud of Turin in 1532, applying a violent chemical test to the cloth in the process. The fire subjected the cloth to a thermal test which revealed that no pyrolysis products of medieval paint compounds were present, ruling out the possibility that the image of the man had been painted. And, despite water being used to douse the flames, the image remained unaltered, indicating it was not water soluble.11


How Old Is It?

In 1988 the cloth was carbon dated to AD 1260 to 1390, but this dating is considered invalid by many Shroud of Turin researchers due to flawed sampling protocol. All three test samples came from a single swatch of cloth cut from near the edge of the cloth rather than by random sampling.12 This area near the edge has anomalous weave patterns compared to the larger body of the cloth. Cotton fibers are mixed with linen in the radiocarbon samples, while the main body of the cloth is entirely linen. Moreover, cotton fibers appeared encrusted with pigment that nearly matches the color of the cloth.13 Altogether, samples used for the radiocarbon tests differ significantly from the main body of the cloth and suggest the samples came from a corner of the cloth that had been repaired by weaving cotton into the linen.

     It is noteworthy that weaving clothing from two different materials goes against Hebrew law (Leviticus 19:19). Similarly, archaeological evidence indicates mixed material textiles were not used for Jewish burial shrouds in Jesus’s time.14

     Physical and chemical characteristics of the cloth offer clues to its age that are not dependent on the carbon dating controversy. Making cloth in the first century started with spinning linen fibers into yarns of thread. When a spindle was full, the hank of yarn would be  bleached. Hanks of yarn were bleached separately, then woven into cloth stabilized with starch during weaving. The linen cloth was then washed with soapweed, Saponaria officinalis.15 Saponaria has hemolytic and preservative properties, explaining why the blood stains appear red rather than black.16 

     Linen threads within the Shroud of Turin are consistent with this ancient spinning and weaving method rather than medieval practices where bleaching was done after weaving the cloth was finished. Additionally, chemical tests on linen fiber growth nodes suggest the cloth is very old and predates the medieval period.17

One Possible Explanation

Evaporation drying after washing would leave a residue of polysaccharides (starch) on the surface of the cloth. Evolving amide gaseous compounds from the corpse could react with the polysaccharide residue by the Maillard reaction. Pigment byproducts from this reaction could bond to the starch residue and produce the image. 

     Chemical tests have confirmed the presence of starch on the cloth. The image color could be stripped off of linen fibers by adhesive tape, indicating that the color resides on a surface residue, not within the linen fiber. The color was removed with the reducing reagent, diimide, leaving unharmed colorless linen, indicating the image color was the result of complex double bonds.18 These findings are supportive of the Maillard reaction hypothesis. If the image was formed by the Maillard reaction, it would indicate the cloth was actually used as a burial shroud but removed from the body before liquid components of decay developed.19


Explanation and the Principle of Economy

Occam’s razor affirms that the hypothesis with the fewest special assumptions is most likely closest to the truth. Elaborate explanations involving radiation or thermal energy must be set aside when the image can be explained by a commonly observed low-temperature chemical reaction. The Maillard reaction offers a plausible explanation for how the image was formed. 

     The Shroud of Turin has physical and chemical characteristics consistent with an ancient burial cloth potentially dating to the time of Christ. It bears the image of a man unmistakably recognizable as the crucified Jesus. The image was not made by human hands. In spite of extensive scientific study, the Shroud of Turin has not been explained away as a fraud or hoax.



  1. Frederick T. Zugibe, The Crucifixion of Jesus: A Forensic Inquiry (New York: M. Evans), 205. The emulsion used by the photographer was more sensitive to blue color than the human eye, inadvertently producing an enhanced photograph. See also Raymond N. Rogers, A Chemist’s Perspective on the Shroud of Turin, ed. Barrie M. Schwortz (self-pub., Lulu, 2008), 17.

  2. Zugibe, The Crucifixion of Jesus, 174–75.

  3. Rogers, A Chemist’s Perspective, 14.

  4. Zugibe, The Crucifixion of Jesus, 240; Rogers, A Chemist’s Perspective, 110.

  5. Rogers, A Chemist’s Perspective, 15–16.

  6. Rogers, A Chemist’s Perspective, 110.

  7. Rogers, A Chemist’s Perspective, 15.

  8. Rogers, A Chemist’s Perspective, 109.

  9. Rogers, A Chemist’s Perspective, 15; Zugibe, The Crucifixion of Jesus, 242.

  10. Rogers, A Chemist’s Perspective, 110.

  11. Rogers, A Chemist’s Perspective, 12, 109.

  12. Zugibe, The Crucifixion of Jesus, 305; Rogers, A Chemist’s Perspective, 7.

  13. Zugibe, The Crucifixion of Jesus, 303–13; Rogers, A Chemist’s Perspective, 64, 66–68, 70, 76.

  14. Orit Shamir, “A Burial Textile from the First Century CE in Jerusalem Compared to Roman Textiles in the Land of Israel and the Turin Shroud,” SHS Web of Conferences 15 (February 27, 2015): 00010, doi:10.1051/shsconf/20151500010.

  15. Rogers, A Chemist’s Perspective, 18.

  16. Rogers, A Chemist’s Perspective, 19.

  17. The age of the shroud can be estimated between 1300 and 3000 years old. Raymond N. Rogers, “Studies on the Radiocarbon Sample from the Shroud of Turin,” Thermochimica Acta 425, nos. 1–2 (2005): 192, doi:10.1016/j.tca.2004.09.029; full article available at (accessed March 2, 2021). See also Raymond N. Rogers and Anna Arnoldi, “Scientific Method Applied to the Shroud of Turin: A Review,” (accessed February 12, 2021): 15–16; Rogers, A Chemist’s Perspective, 41–42.

  18. Rogers, A Chemist’s Perspective, 109.

  19. Rogers, A Chemist’s Perspective, 102.

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