In the early 17th century, a series of highly successful alchemical treatises were published under the name of Basil Valentinus (Latin: Basilius Valentinus), a fifteenth-century Benedictine monk. The Last Testament consists of Books I, II, III, IV, and V of the testament of Basil Valentinus, in which he describes the mines, how they came to exist, and their nature and properties.
Basil Valentine, believed to be a pseudonym, was an alchemist in the 15th or 16th century. However, there is no concrete evidence of his existence before 1600. It was later suggested that Johann Thlde, a German salt manufacturer, may have been one of the authors behind Valentine's works. Regardless of his true identity, Valentine showed extensive knowledge in chemistry, discovering the production of ammonia, hydrochloric acid, ethyl chloride, and sulfuric acid, among other accomplishments.
The Twelve Keys is a widely reproduced alchemical book attributed to Basil Valentinus, 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.
