Iron, Water and Fire
For centuries, boiling water in Japan meant a vessel of iron over an open fire or a charcoal brazier. In the north of Honshu, in Iwate Prefecture, a cast iron tradition grew up that is now known as Nambu ironware. The name comes from the Nambu domain that governed the area in the Edo period, whose lords are traditionally said to have encouraged local metalwork. The best-known centers are Morioka and the Oshu area, which have long histories of iron casting, and the two places have their own styles.
Local conditions favored the craft. The region has traditionally been associated with sources of iron sand, clay and charcoal for making molds and fuel, though precise early details are debated and are best treated cautiously. The result was a community of foundry workers who made kettles, pots, bells and other everyday goods and who, over time, became known for finely finished work.
Two Kinds of Kettle
The word “kettle” covers two related objects.
- Tea-ceremony kettles (chagama) are wide-mouthed vessels with no spout, used to heat water in the tea room. They sit on a hearth or brazier, and the host dips water out with a ladle. They are designed to be seen, and they are discussed with as much interest as other tea utensils.
- Pouring kettles (tetsubin) have a spout, a lid and an arched handle, and they are used for heating water for ordinary tea. They are commonly said to have developed from the tea-ceremony kettle during the Edo period, as steeped leaf teas became popular and people wanted a vessel that could pour as well as heat.
Both are made of cast iron. The two forms meet different needs: one belongs to formal ritual, the other to the table. Where the Japanese tea ceremony values a restrained, calm presence, a pouring kettle can be sociable and decorative.
How a Kettle Is Made
The process is typically described in several stages, though details vary among workshops.
- Making the mold. Fine casting sand mixed with clay is pressed into a form, and the pattern of the outer surface is cut or pressed into the mold. A separate core shapes the inside. Molds are generally used once, since they break apart when the finished piece is removed.
- Melting and pouring. Iron is melted at very high temperature and poured into the mold between the outer shell and the core. This stage is hazardous and is carried out by trained workers with protective equipment.
- Finishing. After cooling, the mold is broken away. The surface is cleaned, the rim is shaped, and the lid and handle are fitted. The inside may be treated so that it is protected from rust.
- Surface treatment. The outside is often heated and coated to produce a dark, even finish, sometimes with lacquer or other traditional treatments.
Because every mold is destroyed in making a single piece, every kettle is slightly individual, and surface details come from the mold-maker’s hand.
Patterns and Their Meanings
Many Nambu kettles are covered in rows of small raised dots, known as arare, a word for hail or small rice crackers. Other surfaces are smooth or carry patterns of flowers, waves, grasses or geometric lines. The dots give texture and a good grip, and they also create a lively surface that catches the light. Some people suggest that the pattern increases surface area or helps with heat, but this is not a claim worth relying on.
Shapes also vary, from rounded and compact to tall and slim, and handles are often cast with their own decoration. The overall impression is often one of weight and solidity, and for many people this heft is part of the pleasure. This may be seen as an expression of wabi-sabi, which treats a worn, slightly rough surface as beautiful, and kettles that have darkened over years of use are often preferred.
In the Tea Room and at Home
In a tea gathering, the kettle has a special role. It sits on the hearth, and its quiet simmering sound is one of the pleasures of the room. In classical writings on tea, the sound of water in an iron kettle is compared to wind in pines, an image that suggests how seriously the sound is taken. The host chooses a kettle to suit the season and the occasion, and a sensitively chosen kettle contributes to the whole atmosphere.
In farmhouses, a kettle hung above a sunken hearth often provided hot water for the household throughout the day. Today, pouring kettles are still used for brewing green tea varieties and are also found as display pieces, while some people use them to heat water on the stove and others use modern, enamel-lined versions designed for convenience.
Care and Cautions
Iron rusts when left wet, so a kettle needs some attention. In general, users are advised to follow the maker’s instructions: empty the kettle and dry it with its lid off after use, and avoid soap or abrasive cleaners that can damage the inner surface. Some kettles are lined with enamel and are made for use on modern stoves, but others are meant for open flames or specific types of heat. A hot cast iron kettle is heavy and can cause severe burns, so handle it carefully. Claims about health benefits from cooking with iron are sometimes made, but they are uncertain, and a person with a medical question should consult a qualified professional.
A Craft That Adapted
Cast iron makers have dealt with changing tastes by adding colored finishes, smaller sizes and new products. At the same time, many continue the old forms. The tradition shows how an everyday object, made well, can gather cultural meaning, and in northern Iwate the heavy pour of iron into sand remains a living craft.