Art Nouveau diamond gypsy ring. Centrally set with a cushion shape old mine diamond in an open back rubover gypsy setting with an approximate weight of 0.55 carats, to a solitaire design with curved tapering bezel, polished borders and pierced geometric backholing, the smoothly integrated shoulders flowing to a solid D-shape shank. Marked 18 carat yellow gold, numbered '1789', French, circa 1890.