A BLACK OPAL AND DIAMOND CLUSTER RING LONDON 1975The oval cabochon black opal within a surround of brilliant cut diamonds, approximately 0.48 carats total, the 18 carat gold shank stamped with sponsor's mark H.B & Co for H A Byworth & Co. Size/dimensions: panel 1.7cm long, finger size IGross weight: 4.4 grams品相报告: The ring setting has some surface wear, scuffs and scratches, the opal has a few small scratches, the diamonds are bright and lively, clarity mostly VS, commercial white. The setting is mostly white gold but there is a yellow gold oval hoop to the back of the setting.