Collectible coins, also known as numismatic coins, are coins that are valued for more than just their face value due to their rarity, historical significance, artistic design, or condition. In the United States, collectible coins include a wide range of types, such as vintage coins, commemorative coins, and bullion coins. Among them, key dates, mint errors, and low-mintage coins are particularly sought after by collectors. The grading of these coins plays a crucial role in determining their value, with higher grades typically commanding higher prices in the market.