Lot 3245^Y. Conch Pearl, Strombus gigas or "Queen Conch", Caribean Sea. Weighing approximately 7.0 carats and measuring 13.02 x 8.73 x 7.94mm. Estimate US$ 7,000 - 9,000 (€ 5,900 - 7,600). © Bonhams 2001-2018

A conch is one of a number of different species of medium-sized to large saltwater snails and their shells. True conchs are marine gastropod mollusks in the family Strombidae, and the most well known species is the Strombus gigas or "Queen Conch". The pearls they produce are calcareous concretions—that is they are non-nacreous and are made up of calcium carbonate (rather than aragonite which is the composition of nacreous pearls). The present pearl is of deep rose color, having a slightly undulating surface to the classic oval shape, with excellent flame pattern iridescence, with excellent surface luster. 

Bonhams. THE WORLD OF GOLD, OPALS AND OTHER "PHENOMENAL" GEMS, 15 May 2018, 10:00 PDT, LOS ANGELES