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Cultivation process

Selecting the mother pearl oysters

Around October

 Good quality pearls are born from good mother pearl oysters. We select the mother pearl oyster for nucleation and the cell pearl oysters with excellent genes.

 In the Shimonada area, our fishing ground, pearl cultivation and seedling production of Akoya pearl oysters are carried out, and if you include the neighboring town of Ainan, it accounts for the majority of mother-of-pearl cultivation in the country.

Preparation of mother pearl oyster

April to July

Putting a nucleus into a mother oyster is like putting a softball into a person's body, and it is a considerable burden. The shellfish are anesthetized in the same way that people are anesthetized, so to speak.

In addition, if eggs remain in the  pearl oyster at the time of integumentation, the color of the pearl will be adversely affected, so the water temperature is adjusted and special equipment is used to encourage ovulation.
A good or bad tailoring technique will have a great impact on the growth of the shellfish in the future.

Insertion nucleus 

April to July

Insertion nucleus is the first and last step in a person's direct contact with the mother pearl oyster. Hence, it is the most important work process in which craftsmanship can intervene. Inside the mother pearl oyster, the nucleus is made by shaving a freshwater bivalve into a round and inserting the cells of the cell pearl oyster into the proper position.
 No two mother pearl oyster are exactly the same as a person. He instantly grasps the individuality of the pearl oyster and cuts the insertion point with a scalpel through the slightest gap in the mouth of the mother pearl oyster, relying on his sense of touch and experience, and quickly, accurately, and without stressing the mother pearl oyster.

Each person cuts into about 600 mother pearl oyster a day, and it goes without saying that this operation has a direct impact on the quality of pearls, but it also has a great deal to do with the lethality of the oyster and the efficiency of the operation.

 Tensei Pearl Self-healing


April to July

The growth environment of the pearl oysters that have finished Insertion nucleus is changed according to the time of year.

First, the pearl oysters that have been operated on are housed in nets and allowed to rest on rafts where the currents are relatively shallow and calm. Meanwhile, in the body of the pearl oyster, cells surround the nucleus by cell division to form a pearl pouch.

Take it offshore

Around July

   After allowing the pearl oysters to fully rest for about a month, they are transferred to a vertical net and moved to an offshore area rich in plankton to feed and encourage the formation of a pearl layer.
  The conditions for a good fishing ground are: the depth of the water, which makes it difficult to be subjected to sudden changes in water temperature, plankton-rich currents, and minerals flowing in from the mountains due to rain.

 Pearl oyster cleaning

Around July

 It is not possible to operate on a pearl oyster once it has been Insertion nucleus.
 The only way to do this is to rely on the life force of the pearl oysters after they have been shipped out.
 Creating a livable environment for pearl oysters is fishery management. The abundance of plankton makes it more active for other organisms, and barnacles and seaweed attach to pearl oysters. Cleaning it regularly will help keep the shellfish healthy.

 Periodically, the workboat is used to clean the shells.  Special equipment on board the ship is used to remove dirt from pearl oysters by the force of water pressure. At the same time, it has the dual purpose of providing a moderate stimulus to the pearl oysters, encouraging their activity and thickening the pearl layer. If the stains are particularly severe, the pearl oysters will be cleaned by hand, one by one. This steady work maintains the health of the shellfish and nurtures good quality pearls.


​End of December to early January of the following year

  When the snow falls on the Yura Peninsula, it takes about two years to produce pearls with a sufficiently thick pearl layer.
  When the water temperature drops to about 16 degrees Celsius, the shellfish begins to secrete a denser layer of pearls as it stores nutrients in its body. It is called "Kesho-maki" and is a very important final process in pearl formation. It is the quintessence of a pearl artisan to discern the timing of this process, which can only be measured by years of experience.If you make a mistake in the timing of finishing, there will be a big difference in the pearl luster after the product is made.

  The four seasons of Japan nurture the mystery of life and produce beautiful pearls. The pearl oysters are separated into pieces of meat and scallops, and the pieces of meat containing the pearls are put into a meat crusher to remove the pearls. When a flesh crusher crushes a piece of flesh, the pearls fall to the bottom of the machine. Then, the pearls are rubbed together with the pearls by a polishing machine to remove the dirt from the surface.Afterwards, when the water is drained in a special dryer, unprocessed pearls, called  "Namadama ", are produced.

Akoya Pearl Tense Pearl made in Japan
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