From its entry into Europe in the Middle Ages, alchemy proposed to re-create the products of the natural world. The alchemists did not merely try to replicate natural gold and silver – they also attempted to make artificial pigments and other chemicals such as verdigris, vitriol (copper and iron sulfate), tutia (zinc oxide), and sal ammoniac. And during the sixteenth century, the followers of Paracelsus von Hohenheim even gave a recipe for creating an artificial man, the so-called homunculus, to be made in a flask by ectogenesis.

Given the fact that alchemists really did present workable recipes for many pigments used in painting, it is not surprising that Renaissance artists such as Cennino Cennini, Leonardo da Vinci, and Giorgio Vasari culled such recipes from alchemical manuscripts. At the same time, however, Leonardo, Vasari, and other artists expressed an extreme disdain for the alchemists’ claims that they could actually transmute substances and replicate the products of nature.