The three known die marriages of the 1818 half eagle are easy to distinguish since two display very prominent diagnostics. On examples of BD-2, the words STATES and OF in the reverse legend appear as one word. This is the most frequently encountered die marriage of the issue, but we stress that all Capped Head Left half eagles of 1813 to 1834 are scarce, if not rare in numismatic circles. Examples of this type saw widespread melting through the mid 1830s, explaining why this is one of the most challenging of all U.S. gold coin series to collect. Survivors of the 1818 BD-2 variety number only 100 to 125 coins in all grades per the Bass-Dannreuther reference and the experts at PCGS CoinFacts. Many show considerable circulation or surfaces problems, emphasizing the desirability of a charming Uncirculated survivor.

Both dies of this scarce variety are distinctive from those that preceded it, the 1818 BD-1 marriage. The obverse shows the new rendition of Reich's Capped Head design, now thought to have been accomplished by Robert Scot, the longtime Mint engraver who remained after Reich's departure in 1817. His portrait bust of Liberty shows lower relief than Reich's version; Breen also pointed out that the "hair is coarser, [and the] cap [is] more obviously wrinkled." Unlike the 1818 BD-1, which used the scalloped star punch for all 13 of the stars, this obverse uses a non-scalloped star punch for the stars. Aside from an appearance on a dime obverse of 1820, after this year the scalloped star would never be seen again. The reverse is the primary calling card of this variety, with its unusual spacing between STATES and OF that makes the two words look like one. The reverse die that follows this one in the die emission sequence (BD-3) shows so much space between STATES and OF that it has often been described as the result of an overcorrection. All examples of BD-2 are highly prized.

The example to the left was sold by Stack's Bowers Galleries in the D. Brent Pogue Part III Auction, where it realized $211,500.