a ring that was used to identify import ant people

a ring with a seal set into it

Is a ring that was used as a means of identification much the same way a seal was used. The signet ring was engraved with a symbol, a coat of arms or initials or some other identifying marker for that particular person.

A ring that contains a signet or private seal, also called a seal ring.

A signet ring is a ring that was used as a means of identification for relatively important people. The signet ring was engraved with a symbol (a coat of arms or initials) identifying a particular person. Some signet rings also had intaglio-carved seals. The earliest-known signet rings date from ancient Egypt, thousands of years ago.

a finger ring engraved with a signet, seal, or monogram; seal ring