A sapphire and diamond ring. Photo Christie's Image Ltd 2014 Set with an octagonal-cut sapphire, weighing approximately 32.12 carats, to the triangular-cut diamond shoulders, mounted in gold, ring size 8½. Estimate CHF250,000 – CHF350,000 ($286,849 -...

A sapphire and diamond ring. Photo Christie's Image Ltd 2014 Set with an octagonal-cut sapphire, weighing approximately 11.30 carats, to the tapered baguette-cut diamond ballerina mount, ring size 6. Estimate CHF80,000 – CHF100,000 ($91,792 - $114,740)...

A sapphire and diamond ring. Photo Christie's Image Ltd 2014. Set with an octagonal-cut sapphire, weighing approximately 20.20 carats. to the baguette-cut diamond shoulders and bifurcated hoop, mounted in gold, ring size 6½. Estimate CHF40,000 – CHF50,000...

An octagonal-cut Burmese sapphire brooch of 47.15 carats, by Mellerio, sold for $3,648,894 at Christie’s Geneva in May 2012, setting a record price per carat for a Burmese sapphire at auction until last year. Photo courtesy of Christie’s. Centering upon...