Signet rings used to be commonly worn by both men and women. This one by Charlotte Paternoster is, appropriate, a unisex version.

It’s made with 9 or 18 karat gold and set with an approximate 9 x 7 mm treated black diamond.

This is priced at USD$1,399.29 for the 9 karat gold and $1,908.12 for the 18 karat version.