So-Called Dollars are a type of commemorative medal that originated in the United States around the late 19th and early 20th centuries, based on their value resembling that of a dollar. They often commemorate significant events, people, or places and are not official currency but are collected for their historical and artistic value. The Hibler and Kappen reference is linked to the cataloging system for identifying these pieces, particularly in their 2000 publication detailing the various designs and manufacturers. The designation "1900" suggests a specific year of issue, while "Unknown" may refer to the lack of documented provenance or origin for certain pieces in this category.

Item Denomination Series Year Mint
1900 Ct Hk-647b Wm Middletown, 250th Anniv. Sc$1 M Other / Varied So-Called Dollars - Hibler & Kappen 1900 Unknown