NGC Certifies 2010-P Yellowstone 5 Oz. Error

The error coin was discovered while grading a bulk submission of Yellowstone 5 oz. coins.

NGC has discovered what may be the first mint error in the America the Beautiful five ounce series. The coin, a 2010-P Yellowstone, has a matte Specimen finish on the Washington side and a brilliant, lustrous finish on the other. This mint error appears to be unique at present, but it is possible that others await discovery.

There are two types of America the Beautiful five ounce coins issued by the Mint: a lustrous bullion version and a matte collector version. The collector version, designated Specimen by NGC, is produced by the same method as the bullion edition except that it is vapor-blasted in the final stage. These Specimens are also distinguished by a “P” mintmark.

The vapor-blasting process is applied after the coins are struck by “blasting” a compressed mixture of water vapor and ceramic media. On this error, only the Washington side was vapor-blasted but the Yellowstone side was untouched. The Washington side therefore resembles a Specimen while the Yellowstone side appears similar to a bullion issue.

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NGC has graded this error Specimen 69 and the description “With Unfinished Reverse” is given on the label. The coin was discovered while grading a bulk submission of Yellowstone five ounce coins.

NGC had recently identified a 2010-P Grand Canyon five ounce variety, which has a lighter finish than the typical Specimen issues. Those coins are considered varieties as the Mint seems to have made a conscious attempt to use a different type of vapor-blasting, while the Unfinished Reverse Yellowstone is undoubtedly a Mint error.

Questions should be directed to NGC customer service at or 1-800-NGC-COIN (642-2646).

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