Iron

The Metal of War

Mars's metal: force and resolve, and the rust that is the price of hardness with no give in it.

Iron takes the sign of Mars unchanged, and of the seven correspondences it is the least in need of explanation: iron is what weapons were made of, and Mars is the god of war. Alchemy placed it among the base metals, hard and unyielding, rusting where copper greens and gold does not change at all. Its resistance to the fire that refines the others was read as obstinacy rather than strength. The metal and the planet share one glyph because the tradition treated them as one thing under two names.