About Iga Natural Red Clay : Maekawa Junzo

Choosing the right kettle is as important as choosing a teapot. For more details, please see the following link.

How to choose a kettle for delicious tea

 

Clay that enriches the aroma of black and oolong tea

Even with Iga shudei, the properties vary greatly depending on where the clay is collected. The clay we acquired enhances body (richness) and aftertaste (depth).
The term "richness" might be unclear, but it simply means the spread of aroma. When you put the tea in your mouth, the aroma and taste spread softly, feeling very rich.

This type of clay is ideal for fermented teas such as black tea, oolong tea, and pu-erh tea. When used for Japanese tea, the aroma becomes very rich, and the sweetness felt on the sides of the mouth increases.

The richness of tea is greatly influenced by the stems. However, Japanese tea tends to remove stems thoroughly for appearance's sake, so modern Japanese tea lacks richness.

Therefore, brewing Japanese tea with Iga clay changes it to a rich taste like karigane.

Discovering ideal natural shudei in Iga, the land of ninjas

The reason for focusing on Iga clay was that the sake from Iga is very rich in flavor, and Asamiya tea harvested around Iga is also rich, leading us to believe that Iga clay must have similar properties.

While white clay is famous in Iga and Shigaraki, they also produce extremely high-quality natural shudei.

With the cooperation of a company specializing in natural clay, we screened nearly 100 types of raw clay. The clay we found on the top of the mountains in Iga showed very interesting properties.

This clay was collected from a very thin shudei layer, about 10-20cm thick, just below the humus layer near the surface of the mountain. The raw clay had a characteristic yellow color typical of shudei, with a particularly strong yellow hue indicating strong individuality.

However, since it also contained coarse sand, we felt it was necessary to remove these, so we refined the clay to some extent and made test pieces, which showed surprisingly strong body.

The aroma of the tea brewed in this clay spread widely, and the rich aroma was beyond expectations when brewing oolong tea or black tea. Additionally, we conducted tests with clay processed under different refining conditions to optimize the refining method.

(Note) Shudei refers to clay that is yellowish in its raw state and turns reddish when oxidation-fired. In China, red clay in its raw state is called "hongni."
 

Iga natural shudei before firing	Test pieces fired from unrefined Iga clay

We obtained only a truckload of clay

As mentioned earlier, the clay we found is very rare, and even if we bought all of it, we could only get about a truckload.

In its raw state, the clay contains dried grass and sand, so it needs to be further filtered and refined into clay. This requires entrusting it to a specialized refining company to process it into clay.
 

Iga natural shudei before refining	Refined Iga natural shudei

Firing test of the same shudei: The temperature increases to the right.

Performance varies greatly even within the same region

Not all natural shudei is good. Since natural clay literally comes from nature, it contains various impurities such as sand.

In reality, finding one decent clay out of testing ten types of shudei is considered good. Even within the same region, the properties of the clay change dramatically depending on the layer and location.

Some clays enhance the depth and body of flavor, adding richness and sweetness to the taste, while others add bitterness, flatten the flavor, or reduce the body and aroma.

At HOJO, we screen various clays using multiple methods to find natural shudei suitable for teapots.

A part of the various test pieces screened to find the desired clay characteristics.

The quality of Yixing teapots has changed over time

In China, the relationship between the clay used for teapots and the taste of tea has been highly regarded for centuries.

Particularly, Yixing shudei from Jiangsu Province is well-known for its high performance, recognized by tea lovers worldwide. The reason why Yixing clay is superior is not because Yixing artists had exceptional judgment.

Teapot artists are pottery experts, but not necessarily taste experts. The high-quality clay used for making Yixing teapots was identified and demanded by tea connoisseurs and cultural figures who understood the value of teapots.

They continuously demanded better quality from artists, leading to the selection of superior clay and making Yixing world-famous.

In addition to the geological advantage of producing shudei, Yixing belongs to the culturally rich Jiangsu Province. Excellent shudei comparable to Yixing can be found in many places in China.

However, regardless of the quality of the clay, without potters who can process it into teapots and buyers who can evaluate the taste, no place can become the second Yixing.

In recent years, the reputation of Yixing has grown so much that it has become difficult to obtain teapots made from the same quality clay as in the past.

Many modern Yixing teapots are made from blended clay, making it extremely rare to find teapots with the same performance as historical Yixing shudei teapots.

In Yixing

Historically, Japanese teapots have focused on appearance

In Japan, pottery has emphasized the relationship between materials and texture/color, represented by the concept of "wabi-sabi," rather than the relationship between clay and taste.

While many Japanese people believe that clay teapots and clay pots make tea and food taste "mild," the detailed relationship between clay and the degree of mildness, as well as the strength of body and richness, is not well understood, even in famous teapot production areas.

The emphasis on appearance has sometimes led to the use of clay that flattens the taste, reduces body and aroma, or increases bitterness.

 

Performance is unrelated to price or the artist's reputation

When seeking high performance in a teapot, the price or rarity of the teapot is not a criterion. Very expensive, artistic teapots made by renowned artists may not necessarily have better performance if the relationship between clay and taste has not been examined.

Teapot artists are pottery experts but not taste experts. Making high-performance teapots requires collaboration between pottery experts and taste or tea experts.

At HOJO, we believe that finding good clay is crucial to producing high-performance (better-tasting) teapots.

Finding clay means literally searching for clay, not new teapot artists.

Important criteria for finding clay are its impact on the taste of tea and its strength to support the functionality of the teapot.

At HOJO, we evaluate many clays and continuously search for clay that enhances the taste and aroma of tea.

To evaluate the relationship between clay and taste, I knead raw clay into cookie-shaped test pieces and fire them in our company's electric kiln. I then soak the fired pieces in tea to evaluate changes in taste and aroma.
During evaluation, I assess various criteria such as body, richness, and bitterness.

Once I narrow down the clays, I conduct more in-depth tests on the relationship between the fineness of the clay, firing temperature, and taste.

Teapots that allow tea to seep through

Iga natural shudei teapots allow tea to seep through the clay's surface when brewing tea. After brewing tea and leaving it, the surface and bottom of the teapot become moist.

This is because we use natural clay from the mountains of Iga, which is highly porous. Iga clay originally comes from the bottom of Lake Biwa.

The clay particles are coarse, making it highly porous. Traditionally, Iga and Shigaraki clays are fired at very high temperatures.

However, firing at high temperatures causes the clay's components to vitrify, reducing the surface area and making it difficult to fully utilize the clay's performance.

In Yixing, China, there are also highly porous clays, and some famous teapots show tea seeping through.

In the case of Iga natural clay teapots, tea will seep through to some extent initially. We ask for your understanding in using them.

Over time, as tea components and minerals from the water permeate the clay, the pores gradually fill, reducing the seepage.

After leaving tea in the teapot, the bottom half became moist.

 

The black spots on the teapot surface are tea components.

When you start brewing tea in an Iga clay teapot, black spots will appear on the surface.
These are not impurities in the clay, so please don't worry.

As the tea passes through the porous surface of the Iga clay, the rapid evaporation of water leaves concentrated tea components that appear as black spots.

Pouring boiling water over them will return them to tea, and they will have the aroma of tea. For a while after you start using the teapot, please clean the surface thoroughly with boiling water after each use.

Over continued use, the pores will gradually fill, and the tea will no longer seep out.

 

Care for Iga teapots

Due to the clay's water-absorbing nature, after brewing tea, please rinse the outside as well as the inside of the teapot with boiling water to wash away tea components.

For ordinary teapots, simply removing the lid and leaving them out will dry the inside by the next morning. However, Iga natural shudei teapots have a water-absorbing nature, so please dry them upside down.

Be careful not to completely block the opening when turned upside down, as some air circulation is necessary to prevent moisture from remaining inside. Iga natural shudei teapots retain tea components easily, so it's best to use them for a limited range of tea types.

For example, if you use it for ripe pu-erh tea and then brew green tea, you may still detect a faint aroma of pu-erh tea. It's fine to share between similar types of tea like green tea, white tea, and Taiwanese oolong tea, but it's best not to use the same teapot for vastly different teas like black tea and white tea or ripe pu-erh tea and green tea.

However, with thorough washing with boiling water, both inside and outside, you can use the teapot for multiple types of tea without issues.

Requesting Junzo Maekawa for production

At HOJO, we conduct our own unique clay search methods, and after careful evaluation of firing and refining methods, we complete the tea utensils with artists who understand our philosophy and goals.

For producing this series of tea utensils, we asked Junzo Maekawa, an artist from Tokoname, for production.


Junzo Maekawa has a very unique background, having graduated from the Faculty of Engineering at university.
With an artistic perspective and logical thinking as an engineer, he devised various ideas to make the teapots easier to use and to draw out higher performance.

Iga natural shudei is very challenging to work with due to its lack of plasticity.
Even when artists manage to create pieces, two-thirds are damaged during drying or firing.

Because of its challenging nature, Iga shudei has rarely been used for teapots.
Due to the difficulty in working with this clay, it is somewhat more expensive than other teapots.