A Chemical Investigation of the Shroud of Turin

Abstract

Michrochemical testing of materials recovered on “sticky” tape samples taken from the Shroud of Turin was undertaken. The Shroud is a linen cloth, bearing the image of what appears to be a crucified man with the classical stigmata of Christ's crucifixion. The presence of whole blood was established by detection of heme derivatives, bile pigments, and proteins. Although iron in several forms is found over the whole cloth its distribution is shown to be accounted for by natural processes rather than as an added pigment. There is no chemical evidence for the application of any pigments, stains, or dyes on the cloth to produce the image found thereon. The chemical differences between image and non-image areas of the cloth indicate that the image was produced by some dehydrative oxidative process of the cellulose structure of the linen to yield a conjugated carbonyl group as the chromophore. However, a detailed mechanism for the production of this image, accounting for all of its properties, remains undetermined.