A 19th century carved coral intaglio mounted gold ring

A 19th century carved coral intaglio mounted gold ring, the intaglio depicting the head of a bearded man. Pierced foliate shoulders. Size M. An unusual gunmetal colour ring mounted with a small gold disc, size M. A George III gold ring, set with three coral and two turquoise cabochons to the closed-back mount. Size K. And a carved agate oval-shaped intaglio mounted gold ring, depicting the profile of a woman in the Classical manner. Size N1/2.