Nothing is known of its whereabouts for the first 600 years after the disciple John saw it in the empty tomb.The reason for the silence about its existence is probably related to its function.The soil is mixed with water and placed in a centrifuge (a machine that spins it very fast).This separates the lighter pollen from the heavier soil. Graphs are compiled of the types of pollen present in relation to the time-scale being studied.It contains only stains of blood and lymph (a colourless fluid from the tissues), but significantly, the blood group is AB positive, the same as that found by scientists during tests carried out on the Shroud of Turin. Three species of pollen on the Sudarium match the pollen on the Shroud.It contains traces of pollen not only from Palestine, but from Africa and Spain, indicating the journey it took on its way to Oviedo.
Although nothing is known of the first 600 years, according to Bishop Pelagius writing in the twelfth century, the Sudarium was in Palestine until shortly before 614 when Jerusalem was attacked by the king of Persia.
The Sudarium is still preserved in the Camara Santa (Holy Chapel) in the cathedral, being displayed to the public three times a year, on Good Friday, the 14th September (the Feast of the Triumph of the Cross), and its octave on the 21st September.
Unlike the Turin Shroud, the Sudarium holds no image.
Pollen grains are distinctive to each plant species and sub-species, and their tiny and dense structure mean that they survive well in many soil types for thousands of years.
Pollen analysts (or palynologists) extract pollen from soil that has been excavated or removed from the ground in auger-cores. Radiocarbon dating is commonly used to date these layers so that the changing pollen presence over time can be measured.