Pounce

Pounce: While the verb pounce, to jump, is widely used. The are two obscure pounce nouns. One pounce is a talon or sharp tool, sharing a Latin root with puncture. The other pounce is a fine powder dusted onto the back side of a stencil to transfer a design - a precursor of carbon paper. This pounce shares its etymology with pumice.

This was the actual working set, complete with the tiny holes and the marks of the red clay pounce we'd used, miraculously preserved.