Craft: Minting, where coins are used as the raw materials to make more coins.

Quote Originally Posted by SRD on Fabricate
Material Component

The original material, which costs the same amount as the raw materials required to craft the item to be created.
Quote Originally Posted by SRD on Crafting
...pay one-third of the item’s price for the cost of raw materials.
Forget 'wall of iron' or 'genesis,' with this, a level 10 wizard could be churning out millions of gold (or platinum) with every casting, and all he'd need is a single coin to get the ball rolling.

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Gold is ~1200 pounds / cubic foot, platinum is ~1340...10 cubic feet / CL, so 600,000 gold / CL for gold, or ~670,000 platinum / CL for platinum, minus the 1/3 you started with as raw materials.


Also, you could probably use a variation of this to utterly devalue various precious stones (ie diamonds, rubies), so that someone would need several portable holes just to carry the "50 gold worth of diamond dust" needed for a simple spell :P