Systems of Metals in Alchemy

Abstract

Two distinct ways of ordering of the seven ancient metals, denoted as System I and II in this paper, can be found in alchemical sources. In System I metals are arranged with gold in the central position: lead, tin, iron, gold, copper, mercury, silver. This arrangement bears resemblance with Ptolemaic system of planets which could have contributed to the origin of this System. Symmetrical positions of the pairs lead-silver and iron-copper with respect to the central, gold-Sun were supported by practical observations. More widespread System II arranges metals from the least to the most precious ones. In this system gold is always the last member of the series. The ordering of base metals in System II has only one typical feature: in most cases iron precedes copper. Therefore attention was paid to redox deposition of copper from cupric solutions on metallic iron. This reaction was important support of claims that transmutation of metals is possible. Further redox depositions mentioned in alchemical and chemical works are also discussed with special attention paid to the influence of impurities on resulting process. One reaction described in alchemical manuscript was repeated in laboratory to show the possible approach chosen by alchemist.