Sea of Cortez Pearls


Staff member
Jun 3, 2020
The Cortez Pearl is a naturally occurring black Pearl that grows in either the Pinctada Maxima (La Paz black-lipped oyster) or the Pteria Sterna (western-winged rainbow-lipped oyster) in the Sea of Cortez – a long, narrow body of water on the west coast of Mexico that separates the Baja California peninsula from mainland Mexico. These oysters were the only source of Black Pearls from the 1500's until others were discovered near Tahiti in the mid 1800's.

Sea of Cortez Pearls

The History of Cortez Pearls
In 1533, the Spanish Conqueror Hernán Cortez sent the very first expeditions into the area to find the mythical "Sea of Pearls". Soon, the area known as the "Vermillion Sea of Cortez" - officially known as the Gulf of California - produced some of the finest known pearls in the world: the Sea of Cortez Pearl. These prized gems became New Spain's most important export product, with a price so high that their value was more than twice of all other combined exports to the Old Continent: gold, silver and spices. It was at this moment in time when Mexican black pearls came to be known as the "Queen of Gems and Gem of Queens", helping to adorn European nobility like never before.

Origin of Cortez Pearls

Sea of Cortez Pearls originate from two species of mollusks that inhabit the Pacific coastline: the "Panamic Black-Lipped Oyster" or "Madreperla" (Pinctada mazatlanica) and the "Rainbow-Lipped Oyster" or "Concha Nácar" (Pteria sterna). They both are capable of producing pearls of incredible beauty. The "Rainbow-Lipped Oyster" produces pearls of highly unusual coloration and intense iridescence, thus producing a pearl that is clearly distinguishable from all others.

Because of their demand, the natural pearl beds were fished constantly for pearls and pearl-shell. A permanent fishing ban was imposed in 1939 in order to save the few remaining pearl oyster populations, ending up a 400-year reign for the Gulf of California black pearl.

Cultured Production of Cortez Pearls

Nowadays, these cultured pearls are produced in Mexico's Gulf of California: Bacochibampo Bay, Guaymas, Sonora. Pearl culture began in the region in 1993 as a university research program. But a commercial production of 20,000 mabe pearls was achieved by 1996. Loose cultured pearl production began in the year 2000. The only marine cultured pearl farm in the Western hemisphere is a medium-sized farm, with some 200 thousand oysters grown in a suspended culture system, with a yearly output of 3-4 kg of cultured pearls, and 5 thousand mabe pearls.

The Culturing Process for Cortez Pearls
The culture process is continuous and has a minimum production term of 4 years: 2 years for the mollusk's grow-out period, and an additional 2 years for the production of cultured pearls. The pearl seeding operation is proprietary, and known only to the original university research team. Each adult, (2 years old, 8 to 10 cm in diameter) Rainbow-Lipped Oyster (Pteria sterna) is seeded with only one American freshwater shell-nucleus, ranging in size from 2.1 to 3.3 bu (6.5 to 10.0 mm) and a piece of mantle tissue from a donor oyster.


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