Proof coins are minted with special dies and planchets. They are pressed at least two times with higher tonnage than business strikes.There are different types of proof coins,brilliant proof have a mirror look with no frosting effect. Cameo proof that has a mirror background and frosted devices to varying degrees:cameo-deep cameo-ultra cameo.
@John1 just by looking with his trained eyes..he knew business strike. How would the beginner know?
Research and a lot of years of practice.
( I'm no pro, it's just my humble opinion )
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