Iron (♂ Mars)

Iron is the metal of Mars (♂), the planet of war, force, and severance. In the sevenfold metal-planet correspondence, iron carries the martial virtues: hardness, resilience, and the capacity to cut and separate. It is forged only through extremes of heat and quenching — a miniature solve et coagula enacted at the anvil. The alchemists considered iron the most resistant of the base metals to transmutation, as its Sulfur is harsh and impure, requiring the most vigorous operations to refine.