Where Do Black Pearls Come From?

Black pearls, also known as Tahitian Black Pearls, come from the black-lip pearl oyster (Pinctada Margaritifera).

Pearls are layers of calcium carbonate similar to a tree's growth rings. The thinner and more numerous the layers are, the finer the pearl's luster. Shelled mollusks create pearls when irritated by something such as a parasite, organic material or a piece of broken shell.

Black-lip pearl oysters are found across the Indo-Pacific.

Identification

Black-lip oysters are bivalve mollusks meaning they have two shells. Black mother-of-pearl, also called nacre, lines the oyster's inner shell.

Size

The black-lip oyster is enormous sometimes measuring 12 inches across and weighing as much as 10 pounds.

Features

The oyster's size allows black pearls adequate space to grow, therefore, many black pearls on the market are large. Most cultured black pearls are given 2 to 5 years growth before harvest.

Types

Natural and cultivated are two types of black pearls. Most cultivated black pearls are from Tahiti.

History

Before conservation efforts, the black-lip oyster was almost harvested to extinction, not for its pearls but for its black mother-of-pearl popular in making buttons.

Fun Fact

Occasionally, an oyster with white mother-of-pearl will produce a black pearl.

Resources

• Information from the American Museum of Natural History
• Information on Tahitian Black Pearls and Jewelry