A seal or signet ring was used to apply the wearer's personal mark to the sealing wax on a document. The seal then demonstrated the legality of the document and the identification of the issuing authority or individual. Signet rings could be engraved with a coat of arms or crest, an initial, a merchant's mark (a geometric symbol used to mark goods or personal belongings), or a personal symbol. Sixteenth and seventeenth century portraits show signet rings worn on the forefinger or thumb, presumably to make it easy to apply the ring to the wax by turning the hand. They were items of jewellery with a practical function but the use of precious metals and engraved hardstones indicates that they were also signs of status.

The initials RS in reverse were most likely those of the owner.