Collectible coins, particularly in the context of the United States, refer to numismatic items that are sought after by collectors for their historical significance, rarity, and aesthetic appeal. One notable type is the "pattern" coin, which is a trial piece struck to test designs or minting techniques before official production. An example is the 1806 pattern coin, which reflects the design experimentation and technological advancements of its time. Patterns can be highly valuable and are often limited in number, making them particularly desirable among numismatists.