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This is an accessory made with epoxy resin and mainly created by sisters Yukiko and Mikako Tamaru.

These original accessories are made primarily from transparent resin parts with a combination of natural stones, glass beads, felt, and ribbon. One of the same designs looks slightly different because each one is handcrafted. Our concept is to create different designs and pieces that we would want to wear them, and people of all ages can perceive the beauty that lies beyond the accessory itself.



Yukiko Tamaru(Tamaru1go)

Work Life
Specialty: Assembling and combining parts.
What I like about the manufacturing process: Taking the finished resin out of the silicon.
What I don't like about the manufacturing process: Applying resin parts to the mold.
What I'm better at than my little sister: Discovering new materials.
What I can't do as well as my little sister: Sewing machine work and website-related activities.

Personal Life
Favorite activity: Sleeping.
Favorite food: Apples.
Least favorite food: Narazuke.
Weak point: Arithmetic.
Currently engaged in: Weight training, archery, reading Western literature.


Mikako Tamaru(Tamaru2go)

Work Life
Specialty: Finding products that look good on our customers.
What I like about the manufacturing process: Applying resin parts to the mold.
What I don't like about the manufacturing process: Threading a French knot on a hair tie.
What I'm better at than my older sister: Photography and the sewing machine.
What I can't do as well as my older sister: Extremely fine beadwork.

Personal Life
Favorite activity: Going back to sleep.
Favorite food: Rice crackers.
Least favorite food: Grotesque-looking stuff.
Weak point: Getting up early.
Currently engaged in: foreign languages.



Born in Tokyo.
Grew up doing crafts such as knitting and sewing from a young age, partly due to parents who loved working with their hands.

In 1995, while my older sister was working as an office worker and my little sister as a stylist, we began making our own accessories as a hobby using Swarovski and glass beads. During that time, we started wanting beads with our own hues, shapes, floral patterns, and stripes. It wasn't until we thought of making them ourselves that we began making our own with epoxy resin. Afterwards, our products started selling in select shops and variety stores across the country.

April 14th, 1997  Established Tamaru Industries Co., Ltd.
September 3rd, 1998  PREMIERE CLASSE store opening.
September 1st, 1998  "TAMARUSAN" opened in Shibuya.
July 28th, 2005  Ginza branch opened (Shibuya branch relocation.)
September 25th, 2016  Ginza branch closed.
January 1st, 2018  Assembled a workshop, newly opened as "Studio and Shop."


Metal Part

1. Introduction
2. Designing Resin Parts
3. Producing Resin Part Prototypes
4. Producing Pedestals for Putting in Resin
5. Creating Silicone Molds
6. Pouring Resin Into the Mold
7. Completion of Resin Parts
8. Production of Metal Parts
9. From Metal Polishing to Plating
10. Assembly Work
11. Finishing Touch



1. Introduction

In making accessories, rarely do we draw our designs on paper beforehand. The reason for this is because we come up with the shapes and designs as we make the accessories. The few times we do draw out the designs prior to making it, is when we design metal parts of photographs or resin parts of main bodies. We ask a specialized metal processing company and stone-polishing craftsmen for their help, and they require designs and specifications. Production mainly divides into metal parts and resin parts.



2. Designing Resin Parts

Producing the resin parts is the most important process for Tamarusan. When resin is made, the first thing we do is name it. This becomes the series name. Hand-drawn pictures are the most common at Tamarusan. We print these designs on either paper or film, according to the texture of the design. In terms of the final product, the main difference is that it will turn out opaque when printed on paper, and translucent when printed on film. When printed on film, the film will reflect a glow the color of the metal fitting on the bottom, or conversely, the color may toned down, so it is important to proceed while observing the resin's compatibility with the metal fittings. Here, a printed piece of paper is used as a template and scissors are used to cut the paper to the size of the finished resin.



3. Producing Resin Part Prototypes

First, I will draw a design of the shapes of the resin parts I want to make. Next, I will have a stone polishing craftsman process it. Agate and onyx are used for prototypes. Relatively hard stones are selected for prototypes, so it can withstand the many times silicon molds are made from it. When there are many cuts in the stone, light reflects and shines brilliantly. In addition, the refraction of light will change the appearance of the inside pattern. On the contrary, dome shaped surfaces will provide a lens effect to enlarge the pattern on the bottom, so even if two pieces have the same design, if the shape is different, it will mysteriously have a completely different appearance.



4. Producing Pedestals for Putting in Resin

Producing Pedestals for Putting in Resin Molds are made with metal materials so they fit perfectly with each resin part. Materials used are copper, brass and silver. The entire reverse side is patterned with a design using a portion of Tamarusan's logo. Unevenness is attained by etching the pattern, allowing the pattern to clearly rise to the surface, especially when antique plating is applied.


Silicone Molds

5. Creating Silicone Molds

Silicone is used to make the molds. The stone prototype is pasted firmly at the bottom of the container, so it will not move even when silicone is poured in. The silicone is poured in quickly and little by little, in order avoid air bubbles from forming. It depends on the temperature, but it is usually left put for 1 day. Silicone molds become stretched after repeated uses, so they are discarded after 3-4 uses so beautiful resin parts can continue to be made. For larger items, such as resin for loop ties, there are cases when the molds can only be used once.


Pouring Resin

6. Pouring Resin Into the Mold

The base and the curing agent are mixed together well. Once it is warmed up with hot water, mixing becomes better and curing defects can be prevented. In order to further remove air bubbles, the silicone mold is placed on a hot carpet and warmed in advance. During the winter, work is done with the heating temperature set very high. Furthermore, applying hot air with a dryer makes it easier to remove the air bubbles. Because the temperature is higher in summer, it is easier to operate and there are less mistakes compared to winter. The resin is finally poured into the silicone mold. Because the mold is very small, there are times when the resin overflows or there is not enough. To solve this, a wire is used to even out the amount as a whole. Next, all the materials of the series, such as paper, film, beads, etc. is placed inside. Depending on the seasonal temperature, hardening time is 1 to 3 days.


Resin Parts

7. Completion of Resin Parts

After a few days, the hardened resin is removed from the silicone mold. This is the completion of a colorful, original, resin part. I match these parts with different colored metals to see how I can bring out the most brilliant shine as I look towards my next creation.


Metal Parts

8. Production of Metal Parts

During the production of the resin parts, there was no need for any direct fire, but in creating metal parts, a gas burner becomes necessary. No designs are pre-drawn here as well, and the production is done without rehearsal. First, in the case of a hairpin, start from where you cut the brass wire, and process the metal with the flame.


Metal Polishing

9. From Metal Polishing to Plating

Metals that are shaped with fire will oxidize, so we will get rid of the dirty portions by soaking in sulfuric acid. From there, it is polished carefully with a metal brush. After this, it is sent to the plating factory. If it is polished cleanly, the resulting plating will also come clean.


Assembly Work

10. Assembly Work

When the metal parts come back from the plating factory, we begin the assembly process with the resin parts. The 5 main plating colors are "antique gold", "antique silver", and "antique bronze", 24 karat gold plating, and rhodium plating. In addition, nickel free plating which is less susceptible to metal allergy is used (excluding some). Depending on the resin series, the most suitable colors are selected. Blue types match well with antique silver and rhodium. Green and yellow types with antique gold or gold. Pink, red, and oranges match well with antique bronze and gold.


Finishing Touch

11. Finishing Touch

After the resin parts and metal parts are attached with an adhesive, matching natural stones or beads are selected. It is very interesting that they are made, the perfect stone or pearl for each series is naturally decided. This is how the world of one series will expand. As I explained in the introduction, because we do not draw our designs on paper, one of the major pleasures is the unexpected results we achieve in the end.