This is one (albeit debateable) explanation for how the Shroud of Turin obtained its distinctive markings. A Volkringer pattern is a natural imprint caused by a chemical effect similar to that involved in flower-pressing. The explanation goes that Jewish law prohibited that the bodies of those who died a violent death be washed and perfumed. Aloe and myrrh, mixed with sodium bicarbonate, were therefore sprinkled on and under the cloth which wrapped the King of Jews who died an undeniably violent death. The linen thus acted as a kind of blotting paper. According to research, the image is not immediately imprinted, so the Turin image appeared a few decades later when the cloth was being preserved as a relic by the first Christians in their flight from the Roman Legions, across the Dead Sea.
The first studies into this phenomenon were carried out shockingly enough by Professor Volkringer, whose cloth herbals produced in the 1940s are supposedly only now beginning to develop the imprints made in those years.