Although these are described as regular die trial pieces in the standard references, it is more likely that the copper 'trials' of this year were deliberately struck for sale to collectors as 3 complete sets were known to exist including Garrett and a double set was apparently stolen from the Iowa State Historical Museum.
Examples were struck as follows:
Copper from proof dies J596/P660 with about a half dozen known.
Nickel from regular business dies J597/P661 with about 3 known. The 1890 Parmelee coin was called Unc, whereas the 1891 Doughty and 1892 Woodside coin was called Proof. It is unclear if these 3 sales represent 1 or 2 coins.
Silver from regular business dies J598/P662 with only the Reed-Durham Museum and Woodin, Newcomer, Farouk, Dibello-Stacks 5/70, Sieck-B/R 7/81, Bass Foundation coins confirmed.
Photo courtesy of Superior and is believed to be the Garrett coin.