De Rupecissa, Johannes (or Jean de Roquetaillade) (d. ca. 1362)
De Rupecissa, Johannes (or Jean de Roquetaillade) (d. ca. 1362)
Alchemist and ancestor of Montfauçon, the distinguished archaeologist. His name suggests that he was a man of gentle birth, while it is commonly supposed that he was a French monk of the order of St. Francis.
In 1357, presumably because of his alchemistic predilections, De Rupecissa was imprisoned by Pope Innocent VI. Much mystery surrounded his life and death. Some said he was released from prison in 1378 by Pope Urban VI, others that he died in prison. Another rumor was that he was burned at the stake in 1362.
De Rupecissa contributed four volumes to the literature of alchemy and hermetic philosophy: Coelum Philosophorum (1543), De Quinta Essentia Rerum Omniam (1561), De Secretis Alchemiae (1579), and Livre de Lumière (n.d.). These were admired by a number of the author's successors, but their value is literary rather than scientific.