“That die marriage combined the Seated Liberty, No Drapery figure adopted for circulation the following year with a defiant eagle soaring upward, grasping a bundle of arrows in one claw and an olive branch in the other. This eagle die was not used with any other pattern strikings, and it is not known for any denomination other than the half dollar.”
The Judd attribution refers to United States Pattern Coins, Experimental & Trial Pieces by J. Hewitt Judd, edited by Q. David Bowers.
According to NGC, to determine the authenticity, NGC sought out the most extensive collection of Gobrecht sketches and trial strikes, held in the National Numismatic Collection at the Smithsonian Institution’s National Museum of American History.
There, coin dealer, researcher and NGC consultant Jeff Garrett took photos of a hub trial and a die trial, both in brass, of the same eagle device.
“The only difference in design from the new specimen is that both of the Smithsonian’s trials had been reduced to half dollar size and were thus associated with the two known patterns, Judd-80 and Judd-81,” according to NGC. “There were no dollar size impressions of this eagle device.”
The Smithsonian pieces are illustrated in Elvira Clain-Stefanelli’s article “From the Drawing Board of a Coin-Engraver: Sketches by Christian Gobrecht for the Coinage of 1836-1839,” published in 1991 in The American Numismatic Association Centennial Anthology, edited by Carl W.A. Carlson and Michael Hodder.
Also illustrated with Clain-Stefanelli’s article are extremely similar sketches in Gobrecht’s hand of this eagle image, which was designed by artist Titian Peale.
The most significant difference between the trial impressions and the specimen recently certified by NGC is that the latter is not die struck.
“Instead, it is a roughly cut hub reduction made in brass from Gobrecht’s sculpted model,” according to NGC. “The circular lathe lines are present throughout the fields of both the square plate and the dollar-size disc within it featuring the eagle device.