Collectible coins include various types, such as patterns and die trials, which are often produced as experimental pieces in limited quantities. The 1861 Patterns Die Trials were part of a series intended to evaluate new designs and minting techniques. In particular, the Denver Mint played a role in the production of trial pieces during this period, reflecting the coinage policies of the time in the United States. These coins are sought after by collectors for their unique historical significance and rarity.

Item Denomination Series Year Mint
1861 DT$2 1/2 Clark Gruber, Copper K-9 BN DT$2 1/2 Patterns & Die Trials 1861 Denver, Colorado