1830 Large D Proof

The 1830 Large 5D proof half eagle ranks among the supreme rarities of early American proof gold, with Bass-Dannreuther references and PCGS records pointing to a single confirmed survivor. Philadelphia produced the year's circulation half eagle on the reduced-diameter close-collar planchet that William Kneass had introduced in mid-1829, modifying John Reich's original Capped Head Left obverse for the narrower format. Two reverse die marriages were used during the year, separated by the size of the "5 D." denomination logotype. A small number of presentation strikes were prepared from the Large 5D dies, almost certainly intended for diplomatic gifts rather than commerce. No proof figure appears in surviving Mint records; the 126,351 figure shown for 1830 reflects combined business-strike output across both reverse hubs.

Authentication begins with the reverse logotype. Under magnification the "5 D." should show the heavier, broader punch with the thicker D upright and a more open interior loop on the figure 5, contrasting clearly with the daintier Small 5D punch used on the matching variety; punch height runs roughly two millimeters on the Large 5D against a noticeably shorter Small 5D figure. The host coin must weigh 8.75 grams in 0.9167 fine gold with a reeded edge, and a calibrated caliper should read approximately 23.8 millimeters across, ruling out both the pre-Kneass 25.0 mm format and any restruck planchet. Proof-finish indicators include fully reflective mirror fields, sharply squared rims that meet the field cleanly rather than rolling into it, and the wire-edge effect from repeated strikes. Bass-Dannreuther proof-only die attribution and PCGS or NGC encapsulation are essential.

For modern collectors the 1830 Large 5D proof exists almost entirely outside the open market. The single recognized example traces back to Virgil Brand's 1906 acquisition for thirty-three dollars; it brought $229,125 at Heritage in 2014 and crossed again at Heritage during the 2019 ANA World's Fair of Money in Rosemont for $300,027. Even the circulation Large 5D is genuinely scarce, with Bass-Dannreuther estimating only twenty-five to thirty-five business strikes across all grades. Pre-1834 half eagles were melted in vast quantities once the world gold price moved above the U.S. coining ratio, and the 1830 Large 5D was particularly exposed because it was already a small production with limited distribution. See the full Capped Bust Half Eagle series history.