Michael Maier's Medicament Coelidonia - A Possible Explanation of its Composition and Production.

Abstract

The composition and way of production of Michael Maier's medicament Coelidonia, mentioned in his book De Medicina Regia et verè Heroica, Coelidonia, were inferred from indications in Maier's book Viatorium, hoc est, de montibus planetarum septem eu Metallorum. The substance was synthesized by the author in a modern laboratory. It is a lead oxychloride of brilliant yellow colour with a composition of approximately Pb₇O₆Cl₂. The same substance was produced from the 1780s to at least 1825 as a pigment under the names of Patent Yellow, Turner's Yellow and Casseler Mineral-Gelb (Cassel Mineral Yellow).