How are Akoya pearls treated?

[pbazar]

What is maeshori and how are Akoya pearls treated?

[Museum Way Pearls]

Maeshori is a chemical treatment done to akoya pearls. There is not a definitive, single description of maeshori because there are many different way to apply the treatment.

I think it best to first explain the background of maeshori. The word literally means "pre-process." This was done to akoya pearls before they went through other types of more generic processes. Today, this maeshori treatment is used a a luster-enhancing treatment. Chemicals are used and the pearls and chemicals are repeatedly heated and then cooled. This tightens the nacre and gives the pearls a sharper luster. They can be overtreated, however, and this can adversely affect the surface. The treatment is NOT good for the pearls. It dries the nacre, making it more brittle.

There are types of maeshori also done to freshwater pearls and South Sea pearls, but not Tahitian pearls. Tahitian pearls may go through a polishing treatment in Japan, but not the same hot then cold treatment done to akoya or other types of cultured pearls. The name of the polishing treatment done to Tahitian pearls escapes my mind at the moment, but it does enhance the shine, and is only done in Japan. Tahitian pearls purchased and exported directly from Tahiti do not (cannot) go through any treatments.

S. Trotta
Museum Way Pearls, Tahitian Pearl Specialists
Tahitian Pearl Earrings and Tahitian Pearl Jewelry