A conch pearl and diamond ring. Photo Bonhams

Set with an oval conch pearl of pink hue, measuring approximately 11.0 x 8.2 x 8.5mm, within a surround of pear and round brilliant-cut diamonds, flanked by two marquise-cut diamonds to each side, between diamond-set shoulders, mounted in platinum, the diamonds estimated to weigh approximately 1.90 carats in total, ring size 7 - Lot 67. Estimate HK$ 530,000 - 630,000 (€61,000 - 72,000). Unsold

Accompanied by a certificate from Gübelin, stating that the saltwater pink conch pearl is natural. Report number 12031075, dated 12 March 2012 

BONHAMS. FINE JEWELLERY & JADEITE, 26 May 2012 14:00 HKT, HONG KONG, ADMIRALTY