The Twelve Keys of Basil Valentine (German: Ein kurtz summarischer Tractat, von dem grossen Stein der Uralten lit.

'A Short Summary Tract: Of the Great Stone of the Ancients') is a widely reproduced alchemical book attributed to Basil Valentine.

The keys are written in such a fashion as to conceal as well as to illuminate: only a knowledgeable reader or alchemical adept was expected to correctly interpret the veiled language of the allegorical text and its related images.

Chemist and historian Lawrence M. Principe has drawn on knowledge of chrysopoetic symbolism and experimentally tested possible chemical processes and practices which may correspond to several of Basil Valentine's twelve steps.

[2]: 157–8 There is evidence that the "father of chemistry", Robert Boyle, also volatilized gold by following the steps in Basil Valentine's keys.