Platinum, Sapphire and Diamond Ring, Carvin French & Platinum, Emerald and Diamond Ring, Tiffany & Co. Photo courtesy Sotheby's

Platinum, Kashmir Sapphire and Diamond Ring, Carvin French. Estimate 275,000 — 325,000 USD (249,934 - 295,377 EUR). Photo courtesy Sotheby's. 

Centering a cushion-cut sapphire weighing 5.80 carats, flanked by tapered baguette diamonds weighing approximately .60 carat, size 6, with maker's mark.

 Accompanied by AGL report no. CS 63492 stating that the sapphire is of Kashmir origin, with no indications of heating.

Platinum, Colombian Emerald and Diamond Ring, Tiffany & Co., circa 1925. Estimate 250,000 — 350,000 USD (227,213 - 318,098 EUR). Photo courtesy Sotheby's

Centering an oval-shaped cabochon emerald measuring approximately 19.2 by 12.6 by 7.7 mm, flanked by trapeze-cut diamonds weighing approximately 1.60 carats, further set with square-cut diamonds weighing approximately .25 carat, size 6½, signed Tiffany & Co.; circa 1925. With signed box.

Accompanied by AGL report no. CS 60816 stating that the emerald is of Colombian origin, clarity enhancement: minor, type: traditional.

Sotheby's. Magnificent Jewels New York, 21 avr. 2015, 10:00 AM