Natural pearl and diamond ring. Photo: Sotheby's.

Centring on a baroque button-shaped natural pearl measuring approximately 12.60 - 13.88 x 11.67mm, to a stylised mount set with circular-cut diamonds together weighing approximately 2.20 carats, mounted in platinum. Ring size: 6½. Estimation 140,000 — 170,000 HKD 

Accompanied by a Gem report stating that the pearl is natural saltwater pearl, with no evidence of treatment. 

Sotheby's. Magnificent Jewels and Jadeite. Hong Kong | 07 oct. 2013 - http://www.sothebys.com