This set contains all three of the 1997 proof American Eagle one-ounce coins - in platinum, gold, and silver. The Platinum American Eagle was first minted in 1997, and this inaugural issue is also the only release in the Platinum Eagle series in which the proof version has the same design as the bullion coin; in all later issues, proofs have a one-year commemorative design that differs from the "definitive" bullion design.
The platinum and gold coins were struck by the West Point Mint with its W mint mark; their bullion counterparts were struck by the Philadelphia Mint with no mint mark. The silver ounce is the opposite case - the proofs were struck at Philadelphia with a P mint mark, while the bullion coins were struck at West Point or San Francisco with no mint mark.
The set comes in a luxury timber box with a metal plaque engraved with its unique serial number, and with a numbered Certificate of Authenticity signed by Philip N. Diehl, director of the U.S. Mint. | 
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