Lot 442. Fine 11.55 carats Colombian emerald and diamond ring. Estimate  800,000 — 1,400,000 CHF (802,992 - 1,405,236 USD). Lot sold 692.000 CHF / 687.011 $. Courtesy Sotheby's

Set with a step-cut emerald weighing 11.55 carats, the mount accented with brilliant-cut and baguette diamonds, size 591/2, partial Italian maker's mark.