keishi pearl

Keishi pearls are the dominant kind of baroque pearls in the market today. The word "Keishi" is used in the Japanese language to describe something very small, for example a poppy seed could be described as "Keishi".

keishi pearl has a solid nacre component and because of that, each pearl has unusually bright luster.

keishi pearls can be found in many shapes but generally are irregular. Each one is definitely different than the others. Layer upon layer of pure nacre makes the keishi pearls produce a rainbow of colors, and this contributes even more to their appeal. Because they're exotic and unique, keishi pearls are a fashion accessory that makes the wearer stand out.

This kind of pearl can be seen in a variety of colors and shades.

The three ways Keishi pearls produce are the following:

1. Individual epithelium cells form the tiny pieces of mantle tissue (which has been implanted together with the nucleus) separate and move to another place in the soft body of the animal, where they multiply and form a pearl sack. This is where the pearl sack may proceed in the formation of a pearl.

2. Small broken pieces of shell drift into the animal during the nucleus implantation and injure the mantle tissue. The injury leads to the displacement of epithelium cells into the mantle's connective tissue, where they form a pearl sack.

3. The operated mollusk ejects the nucleus while the piece of mantle remains in its place and produces a pearl sack.

cultured keishi pearls

Keishi is a Japanese term referring to the typically small sized seed pearl that is formed as a by-product of the pearl cultivation process. The term became common in pearl trading, and is being used for bigger than seed pearls, which come in various forms such as the button, drop and rounded shapes. Keishi pearls are created when the oyster rejects the implanted nucleus before the cultivation process is complete, or the implanted mantle tissue fractures and forms separate pearl sacs without nuclei. These pearl sacs eventually produce pearls without a nucleus.

This kind of cultured pearl is extracted from the oyster called Pinctada Maxima that is large in size. The size of the formed pearls range between 3-20 mm, with prices not similar to natural pearls. The Bahraini and Gulf pearls are extracted from smaller oysters called Pinctada Radiata, and form in Natural form without human intervention.

The Keishi type of pearl threatens the natural pearl trade not only in Bahrain but also the world, and these pearls are available in great quantity and the quality is far better than natural, since the internal structural composition of Keishi and natural pearls are similar, making it difficult to distinguish between them and causing problems for most of the pearl testing laboratories around the world. Since the Laboratory of Bahrain is one of the world's busiest laboratories in terms of receiving different quantities and varieties of pearls, including the Keishi type of cultured pearl, Bahrain laboratory has taken the responsibility to protect the natural pearl market from this threat, it was one of the first laboratories to notice the problem, and to attribute significant importance to solving the dilema, which has created a situation where on many occasions the Laboratory has been forced to refuse the issuance of testing certificates for this kind of cultured freshwater pearl.

There is a unique way that a keishi pearl can form inside the shell. It is stimulated to grow by planting a bead nucleus into the oyster. A bead nucleus is usually taken from the outer shell of clams and formed to a regular round shape pearl. This bead will then be implanted into the soft tissue of the mollusk. When this irritant is placed inside the mollusk, the production of nacre begins.

Nacre production is the defense mechanism of the shell in order to protect itself from any foreign matter. Nacre is made to wrap the foreign bodies that have entered the shell.