Colombian emerald and diamond cluster ring. Set to centre with a square emerald-cut natural Colombian emerald with minor clarity enhancement in an open back claw setting with a approximate weight of 0.90 carats, further set with twenty-two cushion shape old mine diamonds in open back grain and rubover settings with a combined approximate weight of 1.50 carats, further set with four round eight-cut diamonds in open back grain settings with a combined weight of 0.08 carats. The total approximate diamond weight is 1.58 carats, to an elongated cluster design featuring polished edges, a structural gallery and fancy shape open backholing, leading to raised shoulders and flowing through to a solid D-shape shank. Marked 18 carat yellow gold, maker's mark 'AR', French, circa 1900, accompanied by Gem & Pearl Laboratory report #23234
