Collectible coins include a variety of types, such as patterns, which are test pieces created by mints to evaluate designs before full production. The term "pattern" specifically refers to coins produced in small quantities to showcase proposed designs or denominations. In the context of the United States, coins produced in 1865 at the Philadelphia Mint include several significant patterns, which are highly sought after by collectors for their rarity and historical significance. The designation "P" often refers to the Philadelphia Mint's mintmark.

Item Denomination Series Year Mint
1865 P$2 1/2 Copper J-439 RD P$2 1/2 Patterns 1865 Philadelphia