This Working Group chapter project considered the relationship between alchemy and European painting in the late Middle Ages. The most direct connection is in the synthesis of artists’ materials, and the paper drew upon recipes for making colors written by practicing painters from the twelfth to the fifteenth century. Some of these pigment recipes draw upon alchemical concepts in the description of processes undertaken in the artists’ studio. Other recipes simply refer to pigments as being "alchemical," identifying them generically as being synthetic products. Artists did not need pigment recipes in order to make pigments, and the overwhelming majority of pigments would have been synthesized without reference to any recipe. Pigment recipes were also found in contexts where the practical synthesis of pigments was not undertaken. The presence of pigment recipes in commonplace books suggests that knowledge of the material composition of "alchemical" artists’ colors was not restricted to the workshop. Reference to popular literature suggests that widespread knowledge about the identity of many coloured materials used in painting can be assumed during the period in question. This paper considered the meanings that could be associated with two "alchemical" colors when used in conjunction in a well-defined and often repeated context.
Taking a late-medieval popular point of view on alchemy, this contribution looks at metals as astrological manifestations along with their routine manipulation and the use of metallic compounds in cosmetics, medicine, and painting. It considered how the alchemical nature of colored materials (a red and a green) helped define the function of a spatial boundary (a church rood screen), the significance of which was widely appreciated. It further suggested that the color combination (as a conjunction of opposites) could carry meaning in a vernacular visual language that is related to the visual elaboration that took place within the discipline of alchemy.