Lot 511. Property of a ducal house. Important Colombian emerald and diamond ring. Estimate 470,000 — 745,000 CHF. Lot sold 1,874,500 CHF. Photo Sotheby's 2012

Claw-set with a step-cut emerald, between pear-shaped diamond shoulders, size 60, sizing band, numbered, French assay marks.

Accompanied by Gübelin report no. 12100101, stating that the 17.54 carat emerald is of Colombian origin, with indications of minor clarity enhancement.

Sotheby's. Magnificent Jewels Geneva | 14 Nov 2012