Proof coins were issued for collectors beginning in 1873 and ending in 1883. These are all available today, although the earlier issues, particularly those dated 1873 and 1874, are rare and underrated, as will be explained later in the present study.
The formation of a set of 11 different dates of Proofs is not difficult to do, the main requisite being a checkbook with a substantial balance on deposit. In recent years, particularly since the mid-1970s, strong emphasis has been placed on Proofs in higher grade categories, especially Proof-65, a situation which has resulted in a strong premium being placed on this grade level. Cherrypickers (and all serious numismatists should be such) will pick and choose, and among Proof-63 and Proof-64 coins they may well find some of beautiful aesthetic appearance, at a price which may be a fraction of that of Proof-65 coins.
The 1884 and 1885 trade dollars were probably produced by Mint officers as a favor to William Idler, a Philadelphia coin dealer, presumably after Idler promised to keep them a secret (although Carl W.A. Carlson, for one, has suggested that the 1884s were made under regular procedures). Their existence was not known outside of the Idler family until 1907 and was not published until 1908. More information concerning the 1884 and 1885 trade dollars is given under their respective headings.