What Is Nambu Tekki?
Nambu Tekki is a traditional craft of cast ironwork, nurtured in present-day Iwate prefecture. Renowned for tetsubin (cast iron tea kettles) that have now become popular both in Japan and overseas, and for chagama, which are round pots used for tea ceremonies, Nambu Tekki is considered world-class craft and a pride of Iwate. In the old days, cast iron was used not only to make tea utensils, but also to create various tools for everyday life, from pots, pans and farming tools to large bells of Buddhist temples, and played an important role in people’s lives. The name “Nambu” comes from Nambu-han, the feudal clan that built a castle in Morioka and ruled the region in the early Edo period. Artisans from Kyoto were first invited by the Nambu clan to make chagama in the mid-17th century, which became the origin of Nambu Tekki.

Morioka is a region rich in resources and materials that are used for iron making; everything that was necessary, such as iron sand, clay, charcoal and lacquer, was available in the area. Taking advantage of these natural resources, the Nambu clan invited artisans and craftsmen of cast ironwork from Kyoto and Koshu, retaining them within the domain to foster development of industry and culture in the region.

The Mizusawa area in the south of Iwate prefecture (present Hada-cho, Mizusawa-ku, Oshu City) also has a long tradition of cast ironwork. In fact, it has a longer history of iron-casting, dating back to the years of the Oshu Fujiwara Family, who flourished in their capital city Hiraizumi in the late Heian period (12th century).

Currently, ironware produced in both Morioka city and Oshu city are registered to carry the local brand name of “Nambu Tekki.”

The Birth of Nambu Tetsubin 
In the Nambu domain, four families of retained craftsmen, the Koizumis, the Suzukis, the Arisakas and the Fujitas, played an active role in making chagama and developing cast ironwork. Around 1750, Nizaemon Koizumi (3rd) came up with the idea of making a small tea kettle with a handle and a pouring spout, which would be more convenient for an open-air tea ceremony than the conventional chagama. This is said to be the origin of tetsubin. Compared to the ceramic kettle that had been used to boil water, the iron tea kettle was a much better heat conductor, and became popular. Eventually, as a unique rust prevention procedure was incorporated in the late 19th century, the Nambu tetsubin started to be widely used.

Tetsubinmoyo-shu (Collection of designs and patterns for tetsubin) of 1867, and the designs of the same period, reassembled in the Meiji period.

This design book dates back to around the late Edo to Meiji period. The drawing of the shape and pattern becomes the “blueprint” for the tea kettle.

Each workshop has its own designs that are handed down over generations.

Pictorial designs, as opposed to geometric patterns, are sometimes made by sticking the drawing onto the surface.

Modernization of Nambu Tekki
Morioka and Mizusawa had each flourished under the protection of the Morioka clan and Date clan; yet with the Meiji Restoration came the abolition of the han system, and deprived of the clans’ patronage, the local industries deteriorated. However, Nambu Tekki gradually revived itself by expanding its market, thanks to the development of distribution infrastructure such as the railroad. Participation in the National Industrial Exhibition backed by Meiji government’s policy to promote industrial growth also allowed Nambu Tekki to regain national acclaim.

The late Meiji period brought some more years of stagnation. However, in 1914, the former head of the Morioka clan Toshiatsu Nambu, who was a cultured man with a passion for the arts, founded Nambu Casting Institute, with an aim to refine the quality of Nambu tetsubin. The first director of the institute was Somei Matsuhashi (1871-1922), who was born in Morioka and studied casting at the Tokyo Fine Arts School, as one of the first year students of the newly founded art school.

A skilled craftsman, as well as a dedicated instructor, Matsuhashi promoted technological innovation of Nambu ironworks, raising its quality to the level of fine arts. The task was passed onto his successor, Manji Takahashi (1880-1942), who also contributed to the modernization of Nambu Tekki.

World War II and the Postwar Years
The Pacific War bought severe damage to the ironworks industry. Following the outbreak of the Second Sino-Japanese War in the previous year, regulations were enforced in 1938 to collect objects made of iron and steel. Scrap metal of all kinds had to be turned in, casting workshops were banned from making kettles, and the craftsmen had no choice but to switch to the war munitions industry. However, local craftsmen who were determined not to let the heritage die down joined together to form a group, working for the preservation of the art of Nambu tetsubin. As a result, the Nambu ironworks managed to survive the crisis of war, and pass their tradition over to the postwar generation. After the war, demand for Nambu Tekki decreased due to drastic change in lifestyles; the increase of aluminum and stainless steel products also impacted the decline of traditional ironware. However, when the Law for the Promotion of Traditional Crafts Industries was enacted in 1974, Nambu tetsubin became the first to be officially designated as Japan’s traditional craft. Recently, tea pots of modern design have become highly valued overseas, and Nambu Tekki is gaining recognition for producing practical kitchenware.   With a history of 400 years and the traditional skills passed down from generation to generation, Nambu Tekki has a distinctive character; each piece of ironware is not at all elaborate or striking to the eye, yet beyond its apparent austerity and sturdiness, there is a certain warmth and coziness that attract the user. It reminds us, somehow, of the local people, who live with simplicity and patience, withstanding the harsh climate of Iwate.
How Nambu Tekki Is Made   Building the Mold
The mold is made based on the design drawing, so that the desired shape will be formed by casting molten iron into the mold. To make a mold, special molding sand is packed inside a cylindrical wooden frame. First the outer layer is packed firmly with rough sand, then finer sand is added, gradually forming the shape.

A separate mold is made for the pouring spout.

The Core

The core is used to form the internal cavity of the tea kettle. The radius of the core is made 2mm smaller than that of the outer mold. The difference in the sizes of the mold and the core will become the thickness of the cast iron. Clay is melted in water and mixed well with sand to make the core. When the core is completely dry, it is covered with charcoal powder

Stamping Patterns

The distinctive patterns that characterize Nambu Tekki are all crafted by hand. To make the neatly embossed dots known as the arare (hailstones) pattern, a special rod is used to stamp small dents, one by one, onto the mold while it is still moist. 。

Some kettles could have about 2000 arare dots. All dots look similar, but their sizes are varied depending on which part of the kettle they will be placed.

Drying the Mold

The molds for the spout and the handle loops are attached to the top mold, then setting the core inside, the bottom mold is fitted onto the top mold. After binding the two molds tightly together, the surface is burnt in charcoal at 800 to 1000ºC to make it completely dry.


The cast iron is melted in the melting pot. When the temperature is raised to 1500ºC, the impurities appear on the surface of the bright red molten iron. Impurities make the temperature inconsistent, causing problems in forming the shape of the kettle, so a rod is used to remove these impurities.


The molten iron is poured into a ladle.

The molten iron is cast into the mold to fill the mold completely and evenly. Wooden planks are used to hold down the molds with the weight of the casters, so that the molds do not yield to the pressure of the cast iron.

Removing the Mold

When the iron cools to some extent, the tetsubin is removed from the mold. At this moment it is still bright red with heat, but will gradually turn silvery grey. By tapping with a hammer and listening to the sound, the caster checks whether the thickness is even. 

Rust Prevention (Kanake-dome)

Once the casting is finished and the core is removed, the tea kettle is baked once again in charcoal at 900ºC. This process of creating an oxide film inside the kettle to prevent rust is unique to Nambu Tekki. Furthermore, the surface of the kettle is covered with lacquer, using a special brush made from bundled water-grass called kugo-hake. Finally, it is coated with rust-preventing liquid made by putting bits of steel in acetic acid and brewed tea, known as ohaguro. Then it is wiped carefully, the handle is attached, and the lid is put in place. The Nambu tetsubin is now complete.

Various tools are used to press patterns. Some tools have been used since the Edo period, handed down with great care.

Kobashi are tools used for handling the extremely hot melting pot.

Kyoto Women's University, Lifestyle Design Laboratory
Credits: Story

With thanks to Morioka Study Museum of Archaeological Site,Suzuki Shuzendo,Iwachu for their cooperation and providing materials.
Text written and supervised by Takako Yoshida, Chief Curator, Iwate Museum of Art
Text for production process by Sakai Editing and Planning
Edited by Motoki Sakai (Sakai Editing and Planning)
English Translation by Kei Kamoshida
Project Director: Shinya Maesaki, Associate Professor, Kyoto Women’s University

Credits: All media
The story featured may in some cases have been created by an independent third party and may not always represent the views of the institutions, listed below, who have supplied the content.
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