Diamonds with a star, a flower, or a four-point clasp.

A popular option on the wedding band options menu is the outer diamond setting.

MITUBACI currently offers three types of clasps and a choice of diamonds: diamonds and colored diamonds.

Each of these will be described in detail.

Star Setting

The first one is hoshidome (星留め).

This is a new fastening method that started in December 2023. It was so popular at our sister store KOBO in Singapore that we introduced it at MITUBACI!

The diamond is carved in four places (top, bottom, left, and right) before being fastened, making it look like a star.

Due to the space required around the gemstone, we accept rings with a minimum width of 2.5 mm for star clasps.

Flower Setting

The next item we will introduce is a flower clasp.

The round shape around the diamond makes it look like a petal.

Diamonds become more decorative and pretty.

Flower clasps are available for rings with a width of 2.0 mm or more.

4-point setting

Lastly, we introduce the 4-point clasp (yonten-dome).

This is the most basic fastening method.

The simple fastening method makes it suitable for any style.

The birthstone clasp shown inside the ring is also a four-point clasp.

Due to tool restrictions on the inside of the ring, all rings are fastened with a four-point clasp.

Special Order

Multiple diamonds can be fastened; if you wish to have more than 5 diamonds, please contact us as it may be difficult to deliver on the same day.


Q1. I want to put diamonds or birthstones in my ring.

A1. Yes, you can take it home.

Please allow 10 to 30 minutes per stone for processing. The time will vary depending on the type of gemstone and the way it is clasped. You may wait in the workshop, or you may come out of the store for a meal, tea, or a stroll.

If you wish to have more than 5 stones set on the surface of the ring, inside and all together, we may not be able to deliver the ring on the same day. Please understand.

If you are traveling and do not have time, we can deliver the next day, or we can deliver to your hotel or home if you are in Japan.

Q2. Can you deliver to my home? Do you charge for shipping?

A2. Yes, we can deliver within Japan. We will send it to you free of charge. For outside Japan, please consult with us as it depends on the country.

Q3. Are the diamonds real?

A3. Yes, we use natural diamonds.

Q4. What colors are available for colored diamonds?

The colored diamonds handled by A4.MITUBACI are

These are ice blue diamonds, ice green diamonds, black diamonds, and pink diamonds.

Q5. Can I have diamonds or gemstones that I brought myself clamped?

A5. We are sorry, but we do not allow processing with materials you bring in.

Q6. Can birthstones other than diamonds be fixed?

A6. Blue sapphires, pink sapphires, and rubies can be fastened on the front of the ring.

Other birthstones are softer and are not recommended for daily use wedding rings.

Q7. How do you put in the jewelry? Do you use glue? Can they be removed?

A7. We do not use any glue to fasten the gemstones, which are carefully fastened one by one by our craftsmen.

A tiny drill is used to make a minuscule hole in the finished ring, and the gemstone is set in it. A tool called a nanako is used to lay down and support the metal around the gemstone. The gemstone cannot be removed unless the ring is deformed or subjected to a strong impact.

If you have any other questions, please feel free to contact us at

Diamonds with a star, a flower, or a four-point clasp.
Experience the handmade.

All of MITUBACI handmade jewelry courses are conducted by professional artisans.
All our final prices are indicated on our website for your consideration with ease.


Refer to the price list on our website for a detailed breakdown with no hidden cost.