So-Called Dollars are a category of collectible coins that are not official currency but were issued as commemoratives or souvenirs, often to mark significant events or anniversaries. The term "So-Called Dollar" originates from the fact that these pieces are usually dollar-sized and are often associated with commemorative events in U.S. history. An example is the 1949 So-Called Dollar, which commemorates the opening of the International Exposition in San Francisco. These coins can vary widely in design, composition, and collectibility, appealing to numismatists and history enthusiasts alike.