A privy mark is a special symbol that gives information about a coin’s production. According to the Royal Mint, the practice of creating privy marks—or “hallmarking,” as the Brits call it—began as an anti-counterfeiting measure in the 1200s. Jolly good!
In the 19th century, the U.S. Mint used arrows on coins to signal changes to how much silver was in a particular coin.
In the 1920s, the Mint engraved privy marks for the Alabama Centennial Half Dollar, Missouri Centennial Half Dollar, and Grant Commemorative Coin Program. These marks were used for collectible reasons and also to convey that Alabama was the 22nd state and Missouri was the 24th state in the Union.
Today, mints use privy marks for a variety of reasons, including commemorating events and for marketing purposes. Over the past 20 years, the Mint has included privy marks on popular products such as quarters with "V75" privy marks, American Innovation $1 Coins, the 230th Anniversary Flowing Hair Gold Coin, and several 2025 American Eagle Silver Proof Coins.