Although described as regular dies trial pieces, these were actually deliberately struck for sale to collectors as part of complete aluminum sets.
Only 2 examples are known as follows:
1) Heritage 6/2005, southern collection, Simpson-Heritage 4/21 - PCGS66
2) Crouch-Superior 6/77, Denali, Heritage 8/13 - PCSG66
Older pedigrees for these are ex Newcomer and ex Brenner-1914 ANS, Brand (journal #92500:1722)
Photo courtesy of Heritage.