Twelve Keys: Illustrated Alchemical book

"I, Basil Valentine, brother of the Benedictine Order, do testify that I have written this little book, wherein, after the manner of the Ancients, I have philosophically indicated how this most rare treasure may be acquired, whereby the true Sages did prolong life unto its furthest limit.
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The Twelve Keys is a widely reproduced alchemical book attributed to Basil Valentine, a Benedictine monk who for his achievements in the chemical sphere has been given the title of Father of Modern Chemistry. The Twelve Keys describes the major features and framework of the alchemical process. Each chapter of the book is illustrated.