"philosophers' stone": Occultism & Parapsychology Encyclopedia

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"Occultism & Parapsychology Encyclopedia: Philosophers' Stone

A legendary substance which enabled adepts in alchemy to compass the transmutation of metals. Alchemists believed that one definite substance was essential to the success of the trans-mutation operation. By the application or admixture of this substance, often called the 'Powder of Projection,' any metal might be transmuted into gold or silver.
Zosimus, who lived at the beginning of the fifth century, was one of the first to allude to the philosophers' stone. He said that it was a powder or liquor formed of diverse metals, fused under a favorable astrological condition. The stone was supposed to contain the secrets not only of transmutation, but of health and life, for through it the elixir of life could be distilled.
The author of a Treatise on Philosophical and Hermetic Chemistry, published in Paris in 1725, stated: 'Modern philosophers have extracted from the interior of mercury a fiery spirit, mineral, vegetable and multiplicative, in a humid concavity in which is found the primitive mercury or the universal quintessence. In the midst of this spirit resides the spiritual fluid…."