. . . In the back of the Man of the Shroud the hair is apparently arranged in a “ponytail”
shape. . . .  A simpler and more probable explanation is provided by Barta: the “ponytail”
is the result of the use of the Sudarium of Oviedo which was placed and sewed
around the hair in this area. . . .

imageI’ve always found accounts of the coincidences between the Sudarium of Oviedo and the shroud fascinating. Never, however, have I crawled through the details as carefully as I should have.  This paper afforded me a chance to begin that process. This St. Louis conference paper is fascinating. It is worth your time to carefully read New Discoveries On The Sudarium Of Oviedo by César Barta, Rodrigo Álvarez, Almudena Ordóñez, Alfonso Sánchez and Jesús García

Piture: Location of measurement spots on the reverse side of the Sudarium of Oviedo.
The reference numbers are listed in Table III, in the "label" column

I cheat! I jump to conclusions first. But that’s okay as long as I then read the whole paper:

The Sudarium of Oviedo and the Shroud of Turin are two relics attributed to Jesus Christ that show a series of amazing coincidences previously described. These similarities suggest that both cloths were used by the same personality.

In this contribution, we describe the X-ray fluorescence analysis performed on the Sudarium and we highlight a new fascinating coincidence with the Shroud and with the place of the Passion. Among the chemical elements detected, the concentration of Ca is the most reliable one. It is associated to soil dust and it shows a significantly higher presence in the areas with bloody stains. This fact allows us to conclude that the main part of the Ca located in the stained areas was fixed to the cloth when the physiological fluids were still fresh or soon after. As the stains have been correlated with the anatomical part of the deceased man, the amount of Ca can also be related with his anatomical features. The highest content of Ca is observed close to the tip of the nose, indicating unexpected soil dirt in this part of the anatomy. A particular presence of dust was also found in the same place in the Shroud providing a new and astonishing coincidence between both cloths.

The low concentration of Sr traces in the Sudarium, even lower in the stained areas, matches also well with the type of limestone characteristic from the Calvary in Jerusalem.

This new finding complements two other recently publicized: The ponytail shape of the Man of the Shroud hair, whose origin is justified by the use of the Sudarium of Oviedo and the alleged presence of a scourge mark in this cloth.

Such a gathering of evidences strengthens the tradition that both cloths have wrapped the same body, that of Jesus of Nazareth.