What is a signet ring?
Signet rings have been used since the Middle Ages to sign and mark letters (or other objects) with a (personal) wax seal. A seal ring is a ring which is made with an engraving in a seal stone. Engraving usually involves the family crest or monogram (initials) of the family of the wearer. Since the engraving is incised into a surface ( "intaglio"), it can be used to place a mark in a wax seal - after which a print remains with relief.
A signet ring is part of a long tradition of families all over the world, and signet rings are often passed down from generation to generation. There are men's and women's signet rings. The engraving in women's signet rings often have a diamond (single) or oval (married) shape.