Foil blocking, typically a commercial print process now, is the application of pigment or metallic foil to paper where a heated die (engraved metal piece) is stamped onto the foil, making it adhere to the surface and leaving the design of the die on the paper. The foil is often gold or silver, but can also be various patterns or what is known as pastel foil, which is a flat opaque colour.
From the finalised design, metal dies are created in the appropriate shape for each colour foil to be applied. The dies are heated and then stamped with enough pressure to seal a thin layer of foil to the paper.
