Okay, so if you have any idea what a proof cent looks like, imagine the same thing with scratches and hits. That's what one would look like if it were pulled from a bag or roll after circulation. It's really no mystery. The surfaces don't change because the coin is circulated.
Clearing up your post about the dates of proof strikes...
All proof coins from 1950-1964 are Philadelphia mint - no mintmark. Coins were also struck for commerce at the Philadelphia mint during this period.
Proof coins minted from 1965-1967 are not called proof - they are called special mint set coins, and look like proofs. Just like all business strike coins from 1965-1967, the special mint set coins are void of mintmarks.
ALL proof coins minted 1968 and thereafter were made in San Francisco and bear the S mintmark.
Both proof and circulation strike coins were minted in San Francisco from 1968-1974, and bear the S mintmark.
So...all proof cents dated 1975 and after are all S mint coins...all S mint coins minted 1975 and after are proof.
Clearing up your post about the dates of proof strikes...
All proof coins from 1950-1964 are Philadelphia mint - no mintmark. Coins were also struck for commerce at the Philadelphia mint during this period.
Proof coins minted from 1965-1967 are not called proof - they are called special mint set coins, and look like proofs. Just like all business strike coins from 1965-1967, the special mint set coins are void of mintmarks.
ALL proof coins minted 1968 and thereafter were made in San Francisco and bear the S mintmark.
Both proof and circulation strike coins were minted in San Francisco from 1968-1974, and bear the S mintmark.
So...all proof cents dated 1975 and after are all S mint coins...all S mint coins minted 1975 and after are proof.



















