Collectible coins, specifically quarters such as the 1972 Denver Mint coin, fall into the category of numismatics. The term "25c Roll" refers to a roll containing 40 quarters, equivalent to $10. The 1972 quarter features a design of George Washington on the obverse and an eagle on the reverse. Coins from the Denver Mint are marked with a "D" mintmark, indicating their place of production. Collectors often seek these coins for their historical significance, minting details, and potential numismatic value.