Although described as regular dies trial pieces, these were actually deliberately struck for sale to collectors as part of complete off-metal sets.
Examples were struck as follows:
Copper J802/P889 with fewer than a half dozen known.
Aluminum J803/P890 with only 2 or 3 examples believe to exist.
Nickel J804/P891 with only one or 2 known. One is ex Brenner-1914 ANS exhibit, Brand. This or another is ex Edgar Adams-Elder 4/35.
Brass J804A/P892. This may actually be a brassy toned copper example. It is ex Newcomer, Lohr, B/R 9/75, B/R 81 ANA, R. Bourne, private collection. We would like to see the piece undergo SEM-EDX testing to determine its true nature.
Photo is a colorized regular issue proof and is shown to approximate what the die trial would look like. Photo used is courtesy of Heritage.