This coin, part of the So-Called Dollars series as referenced in Hibler & Kappen, is a commemorative piece from the United States, dated 1980. It is classified as a $1 (One Dollar) denomination and is produced in a Proof production type, highlighting its high-quality finish often intended for collectors. The coin is made of silver, a material that adds intrinsic value along with its numismatic appeal. It's important to note that this coin is characterized by a unique lack of specific physical dimensions (width, height, diameter), as well as a weight of zero, which suggests it may not be a traditional circulating coin but rather a special issue or presentation piece. The coin is minted with no mint mark, indicating it was produced without a specific designation of origin, which is typical for some commemorative issues. Additionally, the mintage is recorded as zero, potentially denoting either a limited or unique production circumstance, further enhancing its collectibility. Overall, this 1980 So-Called Dollar embodies a blend of historical significance, artistic merit, and precious metal content, making it a noteworthy addition to any collection of American numismatics.