Ring in pink and yellow gold 750 thousandths, set in its center with a large harlequin opal weighing approx. 15 ct in a surround of two lines of twenty-six 8/8-cut diamonds (estimated H/SI), as well as another set with eight green sapphires and sixteen round and oval-cut tanzanites. Set in the 1950s, transformed. M.O. (partial): Probably Isaak BLACK (inscribed in 1949). Opal size: approx. 20 x 16.5 x 18 mm. Estimated total weight of diamonds/sapphires/tanzanites: 1.30/0.85/1.70 ct Finger size: 52.5 Gross weight: 17.1 g