Collectible coins encompass a wide range of numismatic items, including historical coins, commemorative issues, error coins, and patterns. Patterns are specially made coins that are often struck to test designs or minting processes before official production. In the context of U.S. coins, trial coins like those produced in 1818 demonstrate experimental design approaches, which can include variations in metal composition, size, and weight. These coins are typically produced in limited quantities and are sought after by collectors for their historical significance and rarity.

Item Denomination Series Year Mint
1818-P (Philadelphia) Patterns & Trial Coins Other / Varied Patterns & Trial Coins 1818 Philadelphia
1818-P (Philadelphia) Patterns & Trial Coins Other / Varied Patterns & Trial Coins 1818 Philadelphia