This is one of only 2 pattern half cents. It was struck from the regular dies in two different copper-nickel alloys either 88% copper and 12% nickel or 90% copper and 10% nickel.
Although often called die trials because of the dies used, these are really experimental pieces representing the first use of the listed copper-nickel alloys.
Walter Breen described the first group of these patterns in his Half Cent Encyclopedia:
"On July 11, 1856, a parcel of fifty specimens was sent by Mint Director James Ross Snowden to the Secretary of Treasury to show what the alloy proposed for the new cent would look like, and to distribute them to committee members and others in the Congress, Senate, and Treasury Department. This initial group all show weak borders, being given a single blow apiece in the screw press from dies that were not set close enough together. Many, though with beautiful proof surface, lack relief details on parts of curls, leaves, and sometimes other details. The dentils are never struck up."
About 40-50 are known of which Virgil Brand owned 11.
Photo courtesy of American Numismatic Rarities.