The die is made of heat
treated, hardened steel, and imprints the design on the bullion. The image
on the die is a mirror image of the final design.
The minting dies
are inspected frequently, and polished with diamond paste to maintain a
perfect finish.
The top and bottom dies are locked into
the minting press capable of up to 1000 tons of pressure. The impact
of the dies on the blank within the collar forces the metal to flow
into the recesses of the die and shape the medallion. A proof
medallion requires several strikes to achieve it's beautiful
mirror-like finish.
