Calcareous Concretion

Calcareous concretions are pearl-like growths produced in mollusks that lack nacre. While still composed of calcite and aragonite, the crystals are much coarser. Some of these “pearls” may have a flame-like sheen on their surface. Calcareous concretions seen in jewelry include Conch Pearls and Quahogs.

Calcareous Concretion var. Conch Pearl.

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Pearl Types