Carl Jung on Philosopher's stone

“Explained briefly in more modern terms by Carl G. JUNG, the alchemical process, or Great Work, begins with blackness (nigredo), either present from the beginning or produced by separation of the elements. A union of opposites occurs, often represented by a marriage (coniunctio) of male and female. This union is followed by the death of the product of their union and a corresponding nigredo. At this point, a washing leads to the whitening stage (albedo), which is highly prized as the silver or moon condition. However, this is not the final product, as it must still reach the sun stage or rubedo condition, accomplished by raising the heat of the fire to its highest intensity (pp. 230-2)”

“From this theoretical structure of nature evolved the assumptions upon which alchemy was based: the unity of the universe and relatedness of all natural phenomena as expressed by the idea of prima materia from which all bodies were formed and into which they might again be dissolved, and the existence of a potent transmuting agent capable of promoting the change of one kind of material into another (Fabricius, p. 8). This transmuting agent became known as the philosopher’s stone, an object so quintessential it could not only transmute metals, but cure illness and prolong life....The process was composed of three stages. In the first, the alchemist heated the primary material, usually a blend of salt, mercury and sulfur, until it dissolved and turned black with decay. Under this continuous heat the liquid became dry, powdery and white. If all was done properly, the materials would eventually recombine and become a brilliant red, the color of the philosopher’s stone.”