The regular dies trial piece. Those struck in copper and aluminum were deliberately struck for sale to collectors as part of complete off-metal sets. Those struck in white metal or tin, however, are believed to be true trial pieces. The Judd book mentions the following July 11, 1873 letter from Mint Superintendent James Pollock to Mint Director Henry Linderman: "I send you specimen of trade dollar in tin struck today. We will commence the regular coinage of trade $ in a few hours. The enclosed will give you a tolerably correct idea of the silver dollar." These pieces are listed as follows: To see all available images, click here. Copper J1327/P1472 with 4 or 5 known as follows: 1) ANR 1/06 as PCGS65BN, Simpson-Heritage 1/21 - PCGS66BN 2) Heritage 1/10, Wyoming collection - PCGS64BN 3) Lohr, RARCOA 4/72 - Wyoming collection. 4) Farouk, Dr. Vickery, Paramount 8/72 ANA - Wyoming collection, cleaned, lacquered 5) Harte-B/R 4/81, B/R 1/83 – cleaned, possibly the same as #2 after rehab Aluminum J1328/P1473 with only the former Farouk coin confirmed. White Metal/Tin J1329-J1330/P1474 with a half dozen known as follows: 1) Mitchelson, Connecticut State Library 2) Maryland Rare Coin 1/75 as J1329, Wyoming collection 3) Farouk, Vickery-Paramount 8/72 ANA, A. Champa, Paxman-B/R 11/74, NERCA 12/76, Branigan-B/R 8/78 ANA, State Rare Coins 6/81 as J1330, Wyoming collection 4) Dr. Judd, A. Kosoff (Illustrated History of U.S. Coins #461), unknown intermediates, Heritage 1/06 FUN as J1329, Simpson-Heritage 11/20 (as J1330) - PCGS64, illustrated above, click on the thumbnail image to enlarge 5) Harte-B/R 3/81, Amwest 7/81, Springfield-B/R 12/81, unknown intermediates, Heritage 7/08 ANA, Heritage 11/21 - PCGS genuine, rims filed 6) Burke-B/M 5/94, B/M 9/94 – proof 55 Photo courtesy of Heritage.