Pearls in jewellery

Pearls in jewellery

Pearls form in molluscs. Natural pearls develop without human intervention, while cultured pearls form with human assistance. Cultured pearls are real pearls and must be distinguished from imitations made from glass, plastic or other materials with a pearl-like surface.

Natural, cultured and imitation

Pearls may come from freshwater or saltwater. GIA distinguishes, among others, akoya, South Sea, Tahitian and freshwater cultured pearls. Older jewellery does not automatically contain natural pearls. A white appearance, round shape or expensive clasp does not establish pearl type either.

How is pearl jewellery examined?

GIA uses methods including X-radiography of the internal structure to distinguish natural from cultured pearls. Surface photographs alone cannot answer all such questions. When recording an item, distinguish observations from test results.

GIA assesses size, shape, colour, lustre, surface, nacre quality and matching between pearls. For a necklace, the clasp and stringing are also practical inspection points. Photograph wear, drill holes and damage. A 925 silver clasp establishes its metal, not automatically the pearl type or origin.

Gentle care

Pearls are soft and can be damaged by chemicals, perfume and heat. Wipe them with a clean soft cloth after wearing. Avoid ultrasonic and steam cleaning. If a strung necklace becomes wet, allow the thread to dry completely before use. Browse OBA jewellery.

Sources

GIA: Cultured Pearls; GIA: Pearl Description; GIA: Pearl Identification; GIA: Pearl Quality; GIA: Pearl Care.