From The National Review:
The Shroud, the most studied, analyzed, and tested religious relic in the world, has spawned a vast, global field of scientific study, called “sindonology,” but still baffles scientists. Its mysteries are many and complex. For brevity’s sake, I will only scratch the surface (so to speak). First among the major mysteries is how the image was made. Second, what is the substance constituting the image, which can be scraped away with a razor blade? The substance is undetermined — all man-made materials have been ruled out — and only rests on top of the cloth; it does not penetrate the cloth’s linen fibers. The third mystery is related to the second: Blood from the crucified man penetrated the cloth, as one would expect, but also preceded the impression of the man’s image. “Blood first, image second” is a mantra of Shroud researchers. This order is logical if the “man in the Shroud” was in fact Christ, who would have been wrapped in the linen Shroud days before the electrical event (see below) that accompanied his resurrection and resulted in the human image. The only evidence that would conclusively authenticate the Shroud against naysayers and claims of forgery is Jesus’ DNA. It would be matched against the blood — type AB — found on the Shroud and considered rare. Enter the Sudarium of Oviedo. It resides in the Cathedral of Oviedo, in Spain. The Sudarium is a piece of linen cloth, 34 by 21 inches, thought to have been used to cover the head of Jesus immediately after the crucifixion (John 20:7). Unlike the Shroud, the Sudarium does not display an image. The Sudarium contains male blood of type AB, however, which matches the blood on the Shroud. Moreover, the patterns of blood flow on the Sudarium are consistent with those of a crucified man. Indeed, the Sudarium and the Shroud covered the same person, as Juan Manuel Miñarro, the author of a study sponsored by the Spanish Center of Sindonology, recently concluded. “We have come to a point where it seems absurd to suggest that ‘by happenstance’ all of the wounds, lesions and swelling coincides on both cloths,” said the center’s president, Jorge-Manuel Rodríguez. “Logic requires that we conclude that we are speaking of the same person.”
Meantime, speaking of divine blood: a Eucharistic miracle in Poland has been verified. Check it out.