In another example from the sixteenth century, Samuel Norton gives the following fourteen stages: 1. Others include the Mutus Liber, the twelve keys of Basil Valentine, the emblems of Steffan Michelspacher, and the twelve gates of George Ripley. The Tabula Smaragdina is the oldest document said to provide a "recipe". Various alchemical documents were directly or indirectly used to justify these stages. Though these were often arranged in groups of seven or twelve stages, there is little consistency in the names of these processes, their number, their order, or their description. Similar color changes could be seen in the laboratory, where for example, the blackness of rotting, burnt, or fermenting matter would be associated with nigredo.Īlchemical authors sometimes elaborated on the three or four color model by enumerating a variety of chemical steps to be performed. Birds like the raven, swan, and phoenix could be used to represent the progression through the colors. The magnum opus had a variety of alchemical symbols attached to it. Other color stages are sometimes mentioned, most notably the cauda pavonis (peacock's tail) in which an array of colors appear. After the 15th century, many writers tended to compress citrinitas into rubedo and consider only three stages. The development of black, white, yellow, and red can also be found in the Physika kai Mystika or Pseudo-Democritus, which is often considered to be one of the oldest books on alchemy. Zosimus of Panopolis wrote that it was known to Mary the Jewess. The origin of these four phases can be traced at least as far back as the first century.