Although described as regular dies trial pieces in the literature, it is more likely that these were deliberately struck for sale to collectors as part of complete off-metal sets.
Examples were struck as follows:
Copper J805/P893 with fewer than a half dozen confirmed.
Aluminum J806/P894 with fewer than a half dozen confirmed.
The reverse die used to strike these 2 die trials, is the same overpolished die, used to strike the 1865 dated J418/P490. The polishing wore away some of the lettering. The 2 'S' in 'States', the 'S' in 'Cents', the 'D' in 'United', the 'F' in 'of', the 'A' in 'States' and the second 'A' in 'America' have portions of the lettering polished away.
Nickel, struck on thin planchets J807/P895. It is possible that these are mint errors struck on planchet stock intended for nickel 3 cent pieces. About a half dozen are known weighing between 49 and 59 grains. The example in Superior's 6/2004 sale was not struck from the overpolished reverse die used on the copper and aluminum trial pieces.
Steel or pure nickel J808/P896. This is unique and is ex Brenner-1914 ANS exhibit.
Photo courtesy of American Numismatic Rarities.