Item from Mistborn by Brandon Sanderson
The Allomantic null metal. When burned, it destroys all metal reserves in an Allomancer's body. It blocks emotional Allomancy and cannot be Pushed, Pulled, or detected. In Era 2, the basis of anti-Allomancer technology.
Aluminum occupies a unique position in Scadrial's Metallic Arts — it is the great nullifier. An Allomancer who burns aluminum destroys every trace of metal in their own body, wiping their reserves clean. This seems like a curse, but aluminum also blocks Allomantic effects: an aluminum-lined room blocks emotional Allomancy, aluminum bullets ignore Steel Pushes, and aluminum foil can shield objects from Allomantic detection. In Era 1, aluminum's extreme rarity made it an exotic curiosity. In Era 2, industrial production has made it widely available, revolutionizing security, law enforcement, and combat. The metal embodies how technology can democratize power — the common person's defense against Allomantic manipulation.
A light, silvery-white metal with a soft luster. In Era 1, aluminum was rarer than atium and worth more than gold — only the Lord Ruler's most favored possessed aluminum objects. By Era 2, industrial processes have made it abundant. Aluminum-lined hats, rooms, and ammunition are increasingly common.