Collectible coins encompass a wide variety of types, including those struck by mints for circulation, commemorative editions, and unique varieties like counterstamped coins. In the United States, collectible coins can include issues such as the Four Dollar gold pieces, which were produced during specific historical periods and are sought after for their rarity and historical significance. Counterstamped coins are those that have been altered post-minting by the addition of a stamped mark, often for advertising or promotional purposes, making them unique and collectible in their own right. These coins can carry historical value beyond their monetary worth, appealing to collectors and numismatists.