Feature Gems & Gemology, Winter 1987, Vol. 23, No. 4

The History and Gemology of Queen Conch "Pearls"

Conch "pearls" are calcareous concretions produced by the Queen conch mollusk, Strombus gigas, which is found in various areas of the Caribbean. Although conch"pearls" occur in a range of colors, the pink are usually the most desirable. "Pearls" over 10 ct are rare, but they have been observed as large as 45 ct. They sometimes exhibit a porcelain-like luster and an unusual characteristic called flame structure, which made pink conch "pearls" quite popular in jewelry at the turn of the last century. This article reviews the history of the conch "pearl," discusses S. gigas and its fisheries, and examines the gemological properties and other characteristics of this attractive material.