The 1981has what looks like a mint over and the 1989 had a weak mint mark, multiple die cracks on obverse and reverse one can be seen by eye under mint on rim. The fg are completely different on the coins and both have doubling. almost everything on reverse of the 89 is doubled, the ribbons are also different sizes
Realize that many different dies are used each year to strike those coins. No two are exactly alike. You will find subtle differences in coins struck in the same year. As an example, mint marks were hand punched into finished dies, so from coin to coin, the mint mark will appear in different places on the coin. Other than circulation damage and wear, which is never the same for every coin, I see nothing out of the ordinary. Learn more here: http://www.kennedyhalfdollar.com/
OMM - Over mintmark - example: D over S, O over CC RPM - Repunched mintmark - example: S over S, D over D Chris
Does one have to pass an entrance exam for membership here? The OP came here to learn, he's doesn't seem to be trolling, so let's not ridicule him.
