Mabe pearls are composite cultured blister pearls. They are large semi- spherical pearls that have been grown against the inside shell of the oyster. They have a flat side, so have been called “half pearls.”Why are they called Mabe?
The term Mabe comes from an old Japanese name for the Pteria penguin oyster that is used to produce them. This oyster has been called “Penguin Wing Oyster” or “Butterfly Shell” but it is the Japanese term “Mabe’ gai” that gave the pearls their name.How are they Made?
A half spherical nucleus is glued to the inside of the shell where it won’t disturb the inner soft body of the oyster. The animal will first cover this with a layer of conchioline and then with succeeding layers of nacre. After about 2 years in the case of the Pteria penguin oyster, the nacre will be about 1mm thick. At this time they are cut out of the shell and the nucleus removed. This leaves a hollow half sphere that is very thin and fragile but very beautiful. This is cleaned and filled with resin and the bottom is sealed with a flat base made from mother of pearl.
Mabe pearls are also produced in Pinctada Maxima, which are the oysters that produce South Sea pearls. Usually the farmers use animals that have already produced round South Sea pearls. This large oyster can accept up to eight nuclei on each half of the shell. The mantle tissue is carefully lifted and the nuclei glued onto the shell. These will not grow to have the same nacre thickness as the Pteria Penguin. They are only left in the shell about a year and the nacre will be about .3mm thick. The hollows are filled and sealed in the same way as other mabe pearls.Blister Mabes
Some pearls are left attached to the shell and are known as “Blister Mabes.” They don’t have the nucleus removed and have no need to be filled or sealed with any other substance as they are permanently attached to the shell.Colors of Mabe Pearls
Mabe pearls that come from Pteria Penguin are iridescent and may be in tones of light pink, blue and green. Those that come from Pinctada Maxima are usually white or silver like the color of White South Sea pearls, but are also seen in golden tones. Mabe pearls from French Polynesia will be found in the grey tones of Tahitian pearls.Pearl Jewelry Using Mabe Pearls
Beautiful pearl jewelry can be made from mabe pearls due to their large size. They can be between 15 mm to 25mm in size. As they have a flat back and you can see where the mother of pearl layer has been attached to the back they are usually used in jewelry where only the front of the pearl is visible. Earrings, brooches, pendants, cufflinks and enhancers all may contain large beautiful mabe pearls, set in gold or silver to show their beauty without showing the back of the pearl. Sometimes two mabe pearls are glued together to make a two sided, spherical or drop shaped pearl. But the join is visible and would likely be used in a jewelry style that hides it, rather than in pearl necklaces.
Pearl necklaces need to be made of spherical pearls. As the nacre layer is thin they are fragile, so a jewelry style that gives them some support and protection is beneficial.