He has been identified with Eberhard I von der Mark (1305-1387), a law graduate and clergyman, who became chorbishop of Cologne.
[2] He resigned his positions in the Church to marry in 1346 with Maria de Looz-Agimont (ca.1336-1410), whose titles and territories counties were key points in feudal disputes involving Von der Marck family.
They attempted for eight years to fashion the Philosopher's stone out of hen eggshells and egg yolk purified in horse manure.
He traveled all over the known world, including the Baltics, Germany, Spain, France, Vienna, Egypt, Palestine, Persia, Greece, Turkey, and Cyprus, to find hints left by past alchemists.
For example, Trevisanus de Chymico miraculo, quod lapidem philosophiae appellant was edited in 1583 by Gerhard Dorn.