Red King versus Black King

[Paul Ferguson]

"Two kings face each other across a chemical wedding that never ends. One is fire made flesh. The other is earth that has learned to burn. The Red King and Black King are the two primary alchemical opposites representing sulfur and mercury, spirit and soul, the fixed and the volatile. Their union in the coniunctio produces the Philosopher’s Stone. These figures appear across alchemical manuscripts from the 14th through 17th centuries, most famously in the Rosarium Philosophorum (1550) and the works of Basil Valentine."

https://legrandgrimoire.com/guides/alche...explained/