Akoya Pearls

Akoya Pearls: Cultured Pearls From Ocean Shells

Round, smooth, precisely measured and orderly, akoya pearls have the classic look that many find indispensible with business and formal attire. These cultured pearls are grown exclusively in-body in the Pinctada species--- a small oyster that lives in temperate ocean waters. Following WW2, Japanese cultured pearls held sway around the world for several decades. When Japan exported K. Mikimoto’s famous technology to Australia, South Sea pearl cultivation was born. Cultured pearl technology also migrated to China, where it has developed much less rapidly than fresh water cultivation due to the higher skill level required for in-body bead nucleation. Valuation of an akoya pearl is based on perfectionism and size. The shape is usually prized for faithful adherence to the perfectly spherical shell-bead nucleus (generally, freshwater mussel shells are used, preferably from the U.S.A.). Cultivated pearls can range from 3.5 to 11mm, although those falling within the large end of the spectrum are rarely round. Large cultured pearls tend to have more irregularities because they need more nacre coating than small pearls to avoid exposing the nucleus. Until recently, the most universally desired color of cultured pearls was white or white-pink ---colors least likely to occur naturally in shells that are creamy yellow to greenish. Akoya pearls can also be found in naturally-occurring shades of blues and silvers. For many decades in Japan, it was a law that blue akoya pearls had to be "stabilized" (generally with dye) before export, as these colors were known to fade. Recently, it has become possible to find akoya pearls dyed every color of the rainbow.

Buying Akoya Pearls

Always inspect cultured pearls by rotating the entire strand. This will reveal irregularities in shape and help you discover a reflection (moonstone effect) from within the pearl. This occurs when the coating is very thin; such pearls should be excluded from consideration because they are not durable. Japan's cultured pearl industry has shrunk considerably over the last several decades and unfortunately now operates in the red. Cultured pearls size 7.5 mm and below are hardly cultivated in Japan as demand for these sizes is filled by China's operations. In recent years, Vietnam has become a large producer of cultured pearls. Although these pearls may be of good quality, it is nearly impossible to discern origin by merely viewing them with the naked eye. Akoya pearls with adequate-to-thick nacre coating generally retain their beauty through remarkably long use. Such pearls usually deviate somewhat from a perfectly round shape. Slightly ovoid pearls are known as semi-round, while more irregular pearls are referred to as baroque or semi-baroque. Unfortunately akoya pearl marketers chose not to trumpet this aspect. Their aim instead was to promote only 1 quality:" the finest", and that the pearls should be produced in various sizes to match retail price points. Thus, no Japanese farmer had any choice but to make pearls with very thin nacre coating, which saved money and largely eliminated natural irregularities that increase with nacre thickness. Many such pearls, after being subjected to strong bleaching, quickly lost all vestige of nacre coating, and reverted to bare mother-of-pearl beads.

Nearly all akoya pearls are treated with hydrogen peroxide bleach.

This serves 2 purposes:

Spot removal: Exposure to mild bleach will clear the pearl's surface of any minor grey spots.
Whitening: Pearls that appear to be more white than cream, yellow or silver typically fetch a higher price. Because over-exposure to bleach shortens the life of any pearl, this treatment is rarely disclosed to the customer at a retail level.

Until recently, the most desired color of cultured pearls was white or white-pink, which are colors least likely to occur naturally in shells that are creamy yellow to greenish, and even silvery blue. For many decades in Japan, it was a law that blue akoya pearls had to be “stabilized” (generally with dye) before export, as these colors were known to fade.This is no longer the case. Recently, it has become possible to find akoya pearls dyed every color of the rainbow.