In the earliest years of the Mint, dime and quarter eagle reverse dies were used on each denomination–apparently a conscious decision. The planchet sizes were close, 19 mm for the dimes and 20 mm for the quarter eagles.

The diameter of each denomination was later reduced when new machinery was introduced. The dime’s diameter was reduced to 18.5 mm beginning in 1809, and the quarter eagle to 18.2 mm in 1829.

It is not a stretch to imagine the Mint striking a batch of dimes with a few unstruck planchets remaining in the hopper, then striking a run of quarter eagles, a couple of which were struck on leftover dime planchets. Only 0.3 mm separated the size of the two planchets, an imperceptible difference to the casual inspector.

What happened next is fairly obvious: nothing. This piece entered the channels of commerce and circulated as a dime for many years. Only recently and after 54 points of wear did someone notice that the design was inconsistent with that of an 1831 dime. This piece was found in a bag of silver in North Texas, in May of this year.

It is always interesting to scan the “Found in Rolls” column in Coin World. Foreign coins, tokens, silver coins are constantly found in rolls. But an 1831 quarter eagle struck on a dime planchet in a bag of silver?

This is the second example of this off-metal striking that is known. The other piece is high-grade and has a distinguished pedigree including Brand, Opezzo, Farouk, Judd, and Sloss. It has been off the market since 1974, when it was traded privately, then it was withdrawn from the 1979 ANA Sale. Over the years that piece has been listed and delisted as a possible pattern.

It has been listed in the Judd book as Judd-49, and in Andrew Pollock’s reference as Pollock-50. It was also listed in the 1913 Adams-Woodin pattern reference as AW-39. Don Taxay listed it in the 1976 Scott Catalogue as an error.

Regardless of its listing in pattern references, no one seems to have taken the previously known piece seriously as a pattern. Both of the two known coins were struck 30-40 years before the “made to order” rarities were produced by the Mint, so chicanery would seem to be out of the question, especially when one considers the extensive circulation on this example.

There seems to be no confusion about the status of this piece as the USPatterns.com website states: “Although listed by Judd as a regular dies trial piece struck in silver, Taxay describes this as a mint error, struck on a dime planchet which your editor believes is the more likely scenario. At least 2 examples are known … The other [this coin] is the illustrated example where it was slabbed by NGC as a Mint Error.”

This coin will be auctioned at Heritage’s 2008 September Long Beach, CA US Coin Signature Auction #1116