A small quantity of 16,557 specially made Proof silver dimes were produced at the Philadelphia Mint in 1941. These premium-quality collector versions of the 1941 Mercury dime were struck using specially buffed and polished Proof dies and coin blanks. Each Proof is struck at least twice, at slow speed and with extra pressure. The result is the magnificent Proof finish of frosted, sharply struck design images contrasted against shimmering, mirror-like surfaces.