By Mike Byers for Mint Error News ……

1973-S Proof Kennedy Half Dollar

Struck on Copper Planchet on Obverse

(Bonded Pair)



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This bonded pair of a Proof Kennedy half dollar and a 1.6-gram copper planchet is unique and visually breathtaking. A Kennedy half dollar planchet and a copper planchet were both intentionally placed in the collar at the same time and were struck by Kennedy Half proof dies. The placement of the copper planchet was perfectly positioned in the center of President John F. Kennedy’s portrait.

Mike Byers Mint Error News - Unique Proof Kennedy Half Bonded PairThis unique Kennedy Half bonded pair was sitting in an old-time collection for decades. It was very recently authenticated and certified by NGC. It is in superb Proof condition – which is unusual since copper tends to oxidize and/or deteriorate. As far as I know, this is the only known Proof Kennedy Half bonded pair where another planchet, whether U.S. or foreign, was struck into either the obverse or reverse.

Mike Byers Mint Error News - Unique Proof Kennedy Half Bonded Pair

Proof coins are struck by technicians who hand-feed the blanks into special presses. They are produced, examined, and packaged using extreme quality control. It is very unusual to find major Proof errors. A few broadstrikes, off-centers, double strikes (in collar), and off-metals have been known to be found in sealed Proof Sets. Proof errors are aggressively sought after by many error collectors.

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  1. Is something like this legal to own since it was intentionally done by a mint employee? Could this still be done today?


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