Shiro Shinjyu

Shiro Shinjyu

“The pearl” emanates grace and brilliant shine.
Full of natural beauty and exuding pearly luster,
“SHIRO SHINJYU” is proof of I-PRIMO's emphasis on quality.



Emphasis On Natural Beauty
Unprocessed and Undyed Pearls

Many pearls are soaked in dye, yet I-PRIMO stands firm on “the natural color of AKOYA pearls.”
Shiro Shinjyu has an inherent, natural beauty that doesn’t require dyeing. Even when worn for a long time, the pearl’s color and luster remain the same. Shiro Shinjyu pursues the pearl’s truest colors, unprocessed and undyed.



Emphasis on Quality
“Koshi-mono” Pearls

We seek high quality pearl jewelry suitable for daily use.
To culture pearls, the pearl farmers will set sail for breeding during the spring and harvest them during the winter. Pearls are categorized into “Tonen-mono” and “Koshi-mono.” The former means the pearls are harvested within the same year the farmer set sail, while the latter means the pearls are harvested in the second year.
The "Koshi-mono" are cultured over a long period of time, resulting in a thick coating of nacre and high durability. Then, from these rare and invaluable "Koshi-mono" we carefully examine them and pick out our pearl selection.
SHIRO SHINJYU is proof of I-PRIMO's emphasis on quality.


Cultivating high-quality Akoya pearls on Iki Island of Nagasaki prefecture.

上質なアコヤ真珠を育む 長崎県壱岐島

Cultivating high-quality Akoya pearls on Iki Island of Nagasaki prefecture.

In order to cultivate superior pearls, it is essential to have a high-quality and nutrient-rich seawater. Iki Island of Nagasaki Prefecture is located in Genkai Sea, where the Pacific Current flows along with the Tsushima Current and eventually enter the Sea of Japan. The tidal water in the area flows endlessly like a river stream, allowing the water for pearl cultivation to circulate. This creates a “premium water environment” that is crucial for AKOYA shellfish.

厳選されたパール Shiro Shinjyu

An Exquisite Selection of Pearls-- Shiro Shinjyu

Only top-notch AKOYA pearls cultivated and selected meticulously from Iki Island of Nagasaki prefecture can become I-PRIMO’s SHIRO SHINJYU.


The shimmer of diamonds along with the elegance of pearl luster is often associated with the glistening moon.
“TSUKISHIRO” is a stylish diamond jewelry collection, incorporating both pearls and diamonds.



I-PRIMO Memorial and trendy jewelry

Providing a wide range of products and diverse designs, making all kinds of anniversaries and occasions shine with sparkles.


  • 1. Top quality that matches important anniversaries

    Thoughts are added in the eternally sparkling diamonds and personalized designs, enabling important anniversaries to unleash distinctive brilliance. We exquisitely select diamonds and materials, and deliver jewelry with our determination on details and chains.

  • 2. Materials available to choose from earnestly

    Materials include white gold, gold, rose gold, platinum, etc. Even with the identical design, it brings out surprising different impression when coupled with materials that have different color bases. Please make a selection according to your own preference and skin color.

    ※Metal materials are not available to all designs.

  • 3. One-of-a-kind customization

    Personalized jewelry for couples or newborns on anniversaries to keep them company. We can integrate either the design of birthstones, name initials, graphics or birthdays and names, offering a variety of jewelry available for customization.

  • 4. Reliable after service

    To enable significant jewelry to be worn for a long time, every branch of I-PRIMO in Japan offers cleaning service as a part of after service. Regular maintenance can keep the beautiful brilliance in diamonds.

  • 5. Pink bow as a symbol of happiness

    Special jewelry is put into a particular original box and packed with a pink bow. Whether given to the love of your life or served as a reward for yourself, a pink box adds a little touch of glamour to the gift.


Walk-in customers are welcome. We recommend reservation to prevent waiting during rush hours to ensure better service and will assist you to choose your once-in-a-lifetime dream wedding ring.