Collectible coins, particularly in the United States, encompass various types, including patterns and trial coins. Patterns are experimental or prototype coins struck to test designs, metal compositions, or other features before mass production. The 1850 Twentieth Dollar (Twenty Dollars) is a notable example, as it was part of a series designed to assess public response to potential new denominations. These coins often have limited mintage and are highly sought after by collectors due to their historical significance and rarity.

Item Denomination Series Year Mint
1850-P (Philadelphia) Patterns & Trial Coins $20 (Twenty Dollars) Patterns & Trial Coins 1850 Philadelphia