Absolutely nothing. There's a specific 16 metals allomancy works on, no more, each with a specific effect. It's not just any metal that will work for allomancy. At best, they'll get a stomach ache. At worst, they get poisoned.
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I am the LORD OF THE CRACK!
Check out said crack:
Takamachi Nanoha of 2814- Green Lantern Nanoha. To START! Now with a TvTropes page!
FATE/Holy Grail War of 2814- The Fifth Holy Grail War with Magical Girl Prisma Illya, in the DCAU, from the above story.
Magical Girl Magistra Erebea Molly- the world's first Dresden Files/TvTropes Crossover.
VENGEANCE! The Musical! The Story of Uchiha Sasuke
--------------------------------------
I am the LORD OF THE CRACK!
Check out said crack:
Takamachi Nanoha of 2814- Green Lantern Nanoha. To START! Now with a TvTropes page!
FATE/Holy Grail War of 2814- The Fifth Holy Grail War with Magical Girl Prisma Illya, in the DCAU, from the above story.
Magical Girl Magistra Erebea Molly- the world's first Dresden Files/TvTropes Crossover.
VENGEANCE! The Musical! The Story of Uchiha Sasuke