Collectible coins, such as the 1866 Patterns, represent a fascinating subset of numismatics, particularly in the context of U.S. coinage. Patterns are experimental coins created to test new designs or compositions before official minting, often produced in limited quantities. The 1866 Patterns are notable for their unique designs and historical significance during a transitional period in American currency. These coins are highly sought after by collectors due to their rarity and the insight they provide into the minting processes of the era.