Rubedo is a Latin word meaning "redness" that was adopted by alchemists to define the fourth and final major stage in their magnum opus.[1] Both gold and the philosopher's stone were associated with the color red, as rubedo signaled alchemical success, and the end of the great work.[2] Rubedo is also known by the Greek word iosis.
^Mantello, Frank Anthony Carl; Rigg, A. G. (1996). Medieval Latin: An Introduction and Bibliographical Guide. Washington, D.C.: Catholic University of America Press. p. 413. ISBN0813208416.
^Shaeffer, Katherine H. Stages of Transmutation: The Visual Rhetoric of Alchemy in Sequential Art.University of Florida. 2009. p.21