1824 1824/2 Overdate Proof

Roughly three to five examples are known of the 1824/2 overdate proof Capped Bust dime, placing it among the rarest coins in the entire Capped Bust proof series and among the major rarities of early United States proof coinage as a whole. The issue carries a Sheldon rarity of approximately R-8, the rarity tier reserved for coins with fewer than a dozen confirmed survivors. An overdate is a date created when a working die already engraved with one year is repunched with digits of a later year, leaving traces of the earlier numerals beneath the new ones. On this dime the underlying 2 from an 1822 die remains visible beneath the 4 of 1824 on properly preserved coins, and on proof strikes that diagnostic shows in mirror-quality detail rather than the softer impression seen on circulation pieces. Mint records group the entire 1824 dime output under a combined business-strike figure, while the proofs themselves were struck in tiny presentation quantities that were never separately tallied, which is why no formal proof mintage exists for the issue. Recent auction appearances have brought results in the high five figures to low six figures whenever a coin in collectible grade has crossed the block.

Authentication of a proof 1824/2 begins with the surfaces, since a genuine proof shows the full proof signature: deeply reflective mirror fields, frosted devices on better-preserved examples (the contrast between frost and mirror is called Cameo when strong), and squared rims with sharp inner borders that no circulation die could produce. The JR-1 die markers cataloged for the 1824/2 overdate must be present and must match those documented on the corresponding circulation strike, since the proofs were pulled from the same overdated die before it entered regular production. The underdigit 2 must sit at the correct position inside the 4 and must show the expected curve at the lower loop; a missing or misplaced underdigit signals a recut or altered piece rather than a true overdate. Weight should fall at the standard 2.7 grams on the .8924 fine silver planchet, and any authenticated example should reside in a holder from a major grading service (TPG is the industry shorthand for third-party grader, with PCGS and NGC the two dominant firms) attributing the coin specifically as "1824/2 Overdate Proof" with a PR prefix (PR denotes proof, parallel to MS for Mint State business strikes on uncirculated coins).

For broader context on Philadelphia proof striking practices, Reich's portrait reduction in 1828, and the place of these large-diameter dimes within early federal coinage, see the Capped Bust Dime series history.