Alchemy
The three alchemical stages preceding rubedo were nigredo (blackness) which represented putrefication and spiritual death, albedo (whiteness) which represented purification, and thirdly citrinitas (yellowness); the solar dawn or awakening.
The symbols used in alchemical writing and art to represent this red stage can include blood, a phoenix, a rose, a crowned king, or a figure wearing red clothes. Countless sources give mention to a reddening process. The seventeenth dictum of the 12th century Turba Philosophorum is one example:
O Turba of Philosophers and disciples, now hast thou spoken about making into white, but it yet remains to treat concerning the reddening! Know, all ye seekers after this Art, that unless ye whiten, ye cannot make red, because the two natures are nothing other than red and white. Whiten, therefore, the red, and redden the white!Rubedo is also known by the Greek word, Iosis.
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