Collectible coins are valuable items sought after by numismatists and investors, often categorized by their historical significance, rarity, and condition. Within the United States, notable types include patterns and trial coins. Patterns, created as experimental pieces for potential future minting, often differ in design or composition from regular coinage. Trial coins from 1870, for instance, serve as prototypes displaying various artistic and technical characteristics intended for official use. The 2 and 25 denominations represent common values found in collectible series but are often more valuable in the context of unique variants or rare editions.