The black Tahitian pearl is a cultured pearl, meaning it has been produced by man through a modern fish farm type of production. They do still come from oysters, in this the case the Black Pearl Oyster (Pinctada margaritifera ) but a process whereby man puts a substance or object inside the shell of the oyster, forcing a pearl to grow, is what is known as 'cultured pearls'.

However the black Tahitian pearl is still comparatively rare and valuable, because back pearl oysters only rarely produce pearls, even when 'seeded' to do so.

Pearls are produced when a foreign object enters the shell of the oyster, which is normally closed but occasionally open to feed. Sometimes it can be a irritant such as a parasite or a piece of broken outer shell of the oyster, after an attack by a predator.

It is rarely a grain of sand as previously thought. The auto-immune system of the oyster kicks into action, and layers of calcium carbonate and conchiolin are secreted to form rings round the foreign object to protect the oyster. Then another layer is formed, and yet another on top. The final pearl is a mass of concentric layers of calcium carbonate. It is because of these layers, or rings, that gemologists can determine a natural pearl from a cultured or fake pearl.

The Black Tahitian pearl is not pure black. They have lusters of other colors through the nacre , or mother of pearl, that they are made from.

Like mother of pearl, all the colors of the rainbow are represented, and finding two Tahitian pearls alike in color, shapes and size is a difficult job.

This is what makes complete necklaces made up of matching Tahitian pearls so expensive.

Nor are all black Tahitian pearls black.

Some are almost white, some are grey-black, or greenish or pinkish or blueish or bronzy in color.

Finding two alike is almost as rare as finding two snowflakes alike.

 

 

 

There is even an official color chart for the black Tahitian pearl.

Peacock – black and green
Fly Wing - metallic green and silver
Rainbow – black, green, and pink or aubergine
Tahitian Gold – black and gold
Champagne - yellow or gold and grey
Aubergine - purple or deep pink
Pigeon Grey – grey and purple
Moon Grey - pale grey
Pistachio – grey and green
Lavender - silver or grey and blue