The Twelve Keys (Paperback)

Basil Valentine's Twelve Keys of alchemy is among the most notorious alchemical works ever crafted. Originally written at the very end of the 16th century, it was almost immediately rendered into English and widely regarded. Containing a series of parables and metaphors regarding the process of creating the Philosopher's Stone, the Twelve Keys claim that alchemy is both real and potent, able to perfect matter and create a medicinal elixir beyond comprehension. Valentine swears that the process is not as others have described, with often vague references to "special" salt and sulfur, but is far easier and much less expensive than claimed in prior works.

Basil Valentine is the Anglicised version of the name Basilius Valentinus. Basilius Valentinus was alleged to be a 15th-century alchemist, possibly Canon of the Benedictine Priory of Saint Peter in Erfurt, Germany. During the 18th century it was suggested that the author of the works attributed to Basil Valentine was Johann Thölde, a salt manufacturer in Germany who lived roughly 1565 – 1624. Modern scholarship now suggests that one author was Thölde, but that others were involved. Thölde published the first five books under Valentine's name. Whoever he was, Basil Valentine had considerable chemical knowledge. He showed that ammonia could be obtained by the action of alkali on sal-ammoniac (ammonium chloride), described the production of hydrochloric acid by acidifying brine of common salt (sodium chloride), and created oil of vitriol (sulfuric acid), among other achievements.