Collectible coins include various types such as commemoratives, bullion, and proofs, which are produced for collectors rather than general circulation. In the United States, denominations range from 1 cent (1c) to 50 cents (50c), with specific issues gaining popularity among collectors. Proof sets, including those from 1991, are specially minted coins characterized by their reflective surfaces and frosted designs, often packaged together for collectors. These sets are valued for their quality and limited mintage, contributing to their appeal in the numismatic community.

Item Denomination Series Year Mint
1991-S 1c-50c Proof Set 1c-50c Proof Sets 1991 San Francisco