Collectible coins and medals encompass a wide range of numismatic items, including currency minted for circulation and medals awarded for achievements or commemorations. In the United States, these can include commemorative coins, state quarters, and various award medals. The Harkness medal from 1884, categorized under Agricultural Mechanical Society Award Medals, is a specific example that represents recognition in agricultural or mechanical achievements. Collectors often seek these items for their historical significance, rarity, and artistic value. The designation "Unknown" may refer to the specific designs or recipients associated with that particular medal or coin.

Item Denomination Series Year Mint
1884-- (Unknown) Agricultural & Mechanical Society Award Medals - Harkness Other / Varied Agricultural & Mechanical Society Award Medals - Harkness 1884 Unknown