A "signet" is a small, special type of ring or seal used to make official marks or impressions on documents. It usually has a design or symbol unique to a person or organization, and its use indicates authenticity or authority. Full definition
During an archaeological dig on Hatteras Island in 1998, archaeologists discovered a 10 - carat gold English signet ring from the 16th century, among other artifacts. (en.wikipedia.org)
A piece of signet jewelry is the most personal piece of gold you can possible gift someone. (alwaysjudging.com)
From the side, the profile of the E 63 4MATIC catches the eye with its arrow - shaped wing signet in silver chrome, bearing the 3D «V8 BITURBO 4MATIC +» lettering. (mercedesblog.com)