A seal is a mark identifying some entity and is placed on documents to show their authenticity. Traditionally they consisted of incuse stamps, which were used to make a mark in hot wax, often "sealing" a ribbon to the page. On current U.S. Federal Reserve Notes the seal is the green (or sometimes red) circle overprinted on the denomination to the right of the portrait. The legend in the outer circle reads "DEPARTMENT OF THE TREASURY 1789" and the center device is a shield divided by a chevron, with a set of scales above and a key below.
thanks for the information i needed that information because i wanted to see my dollar was worth more than its face value and it does
