Yellowstone 5 Oz Silver Coin Error Discovered by NGC


NGC has discovered what may be the first 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 error appears to be unique at present, but it is possible that others await discovery.

2010-P Yellowstone 5 Oz Silver Coin Error
This 2010-P Yellowstone 5 Oz silver coin error discovered by NGC has a brilliant finish on the reverse and the intended matte specimen finish on the obverse. Click image to enlarge.

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.

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. NGC may be contacted by writing to P.O. Box 4776, Sarasota, FL 34230 or by calling toll-free at 800-NGC-COIN (642-2646). NGC’s email address is

About NGC

NGC, the world’s largest and most respected third-party coin grading service, was founded in 1987. From the beginning, NGC has committed itself to developing an impartial, trusted standard of consistent and accurate grading. To uphold this commitment, NGC’s full-time grading experts are no longer active in the commercial coin marketplace, and are prohibited from buying or selling coins to ensure impartiality. As NGC has grown to become the leader in third-party grading services, we have maintained a steadfast and uncompromising commitment to this standard.

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I have a yellowstone quarter in a 2010 silver proof set that is missing the ell in yellowstone the inside of the rim looks like a chunk of metal missing under were ell is it has a black film over area. almost look like the flux on a newly welded area. There is a dip where ell is. I had to buy a second set because I did not want this set in that collection.does any one have any comments or answers