"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 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... 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."