Thank you for visiting HOJO website. If you have any enquiry, please feel free to get in touch with us at
▼ Akira Hojo
▼ Hojo Newsletter
▼ HOJO FACEBOOK
The history of Zi Sha Hu has started at Yi Xing during 正徳 (1506-1521) to 嘉靖 (1522-1566) in Ming dynasty. The tea pot was needed since the tea culture was changing to the modern style at that time. It was more than 500 years after陸羽・LuYu（733～804）introduced 茶経.
In Japan, tea culture was introduced around the time when the 茶経 was published in the late Tang Dynasty. At that time, tea was drunk as one of Chinese medical herbs. Unlike to the conventional brewing, fresh or dried tea leaf was dropped into boiling water and drunk. During宋朝, the 点茶 culture was developed and the compacted tea powder that made from either fresh or dried tea leaf was used. The interesting point is that for this tea culture, the equipment by the name of 湯瓶 or 茶瓶 that was used for boiling water had a side-handle. Even at present, the same equipment is used for Chinese Herbs.
The 点茶 culture was introduced to Japan by 栄西禅師 (1141-1215) who studied in China and published the book in Japan. Thanks to his book, the tea culture was rapidly developed in Japan. Many Kings encouraged his associate people to learn about tea and also developed many tea wares.
In 1600s, the culture Sencha was introduced to Japan by 隠元禅師. With the introduction of sencha culture, tea ware was also introduced from Yi Xing, China. However at that time, it seems Japan already had own manufactured teapot. It was not the tea pot specially designed for Sencha like the Yi Xing 茶壺. The 湯瓶 that was made for 点茶was deeply adapted in Japanese tea culture and used for brewing Sencha. Subsequently the design of Japanese tea pot has further evolved. The design of Yi Xing teapot茶壺 merged with 湯瓶 and became the conventional design of Japanese teapot. The Japanese Teapot is called kyusu 急須, while that teapot from Yi Xing was called cha-hu茶壺. Usually, the side-handle and the outlet is aligned at about 90 degree, however, depending on the artist, the angle is varied.
In Japan, there were 4 major places known for the manufacturing of clay teapots: Mie Prefecture(Banko Yaki 萬古焼), Gifu (Onko 温故焼), Aichi Prefecture (Tokoname Yaki 常滑焼) and Mumyoi Yaki (無名異焼） These 4 areas were located at the center part of Japan. Geographically, all these 4 areas are located along the Japan Median Tectonic Line (JMTL) and Itoigawa-Shizuoka Tectonic Line (ISTL) which is connecting to JMTL. In the history, these places are known to have very active volvanoes. There is no doubt that these areas produce clay with very high minerals content.
In year 1859, Ogaki 大垣（岐阜県） started to make the first clay teapot in Japan and named as Onko Yaki: 温故焼. However, it disappeared in the history and up to date, this is no longer exist. The biggest contribution of 温故焼 is the introduction of potter's wheel method: 轆轤 in making a teapot. Initially clay teapot was made by 打身筒 method that was introduced from China. Banko and Tokoname were also influenced and 轆轤 method is still used until today.
I would like to clarify the terminology of Zisha 紫砂(Purple Sand) once again. Zisha refers to crude clay rock that is purple in appearance. As it has extremely less viscosity, people call it Zisha (meaning purple sand) instead of Zini紫泥(meaning purple clay). The word sha 砂(sand) is meant to indicate that Zisha is a mixture of minerals. Its character is just like sand.
Zisha is the mixture of 3 clays, red clay, purple clay and green clay. Different clay has different effect. Each type of clay has a different mineral composition and therefore makes the taste of tea obviously different. Various interactions or sort of ion-exchange reactions occur between the minerals that exist in water and the minerals in the clay.
Japanese Purple clay could be light red, beige, yellow or purple before baking.
Crude red clay could be in black, yellow, purple or red in color.
Basically there is no difference between red clay and Japanese purple clay, except its iron content.
If clay contains 6-10% of iron, we call it purple clay, while at around 20% we call it red clay.
If you mix about 30% of natural red clay into yellow or white clay, it becomes artificial purple clay.
When iron is baked with oxygen, it oxidizes to become Fe3+ (Magnetite). On the other hand, iron becomes Fe2+ (Hematite) when it is baked with less oxygen or without it entirely. With less oxygen, fire generates carbon monoxide. This carbon monoxide will draw oxygen away from the iron.
Because of the different number of electron with iron Fe2+ and Fe3+, the effect of clay on the taste of water can vary greatly. Each kind of clay usually has 2 different effects, depending on whether “oxidized baking” or “reduced baking” was applied. Hence purple clay is made by reduced baking and red clay, by oxidized baking.
One important fact is that Japanese purple clay is different from Yi Xing purple clay. Japanese purple clay is reduced red clay that dominant mineral is iron, while Yi Xing purple clay consist of Cu, Cr, Zn and Mg. In addition, Yi Xing purple clay is baked in fire with oxygen.
The natural clay and mixed clay gives a different effect. It is possible to artificially produce red clay according to the same mineral composition of natural clay. But there is big difference. The iron particle exists in natural red clay is in granule shape or a kind of crystallized iron granule, just like gem stone. Artificially mixed red clay contains added iron which is ground by granulator. The shape of iron particle is very uneven. Usually artificially added iron has very low melting point because of larger surface and more heat-exchange, which unable the clay to withstand high baking temperature up to >1200 degree C. Natural clay can withstand more than 1200 degree C. Under such high temperature, the clay shrinks a lot. Thanks to the large shrinkage, natural red clay gives a larger surface area. It allows more interaction with the minerals which exists in water.
Nowadays most of red clay teapots both in Japan and China are made from artificially mixed red clay. In Japan, it is only Sado Island that produces the natural red clay teapot.
Using a Japanese purple clay tea ware, the flavor and taste is very much enhanced, yet the aroma is reduced. Because of this character, Japanese purple clay is suitable for the tea which we do not require too much aroma. For example, green tea, yellow tea, puerh ripe tea and flower tea such as chrysanthemum. You may be surprised that purple clay also performs very well with coffee, wine and even whisky.
Using purple clay for oolong, very few customers still enjoy its taste if he/she is a very taste-oriented person. For most of people, the aroma is a very important element for oolong teas. Usually 80% of my customers feel something is missing.
It enhances flavor, yet maintains aroma. The enhancement of flavor using the red clay is not as powerful as that of purple clay. The flavor intensity differs depending on the quality of clay. For example, using artificially mixed red clay, the flavor is very weak, although aroma is good. Good red clay improves flavor a lot and aroma is still well-maintained.
Red clay is suitable for all kinds of oolong including Taiwan high mountain oolong, Wuyi Oolong and vintage oolong, black tea, white tea and raw puerh. It is also very suitable for wine, brandy and so on. Personally I enjoy using red clay bowl for drinking soup. Once I tried it, I am unable to return to using the normal bowl anymore.
Japanese Natural Red Clay Teapot >>
Green clay is a very strange clay. The primary mineral inside green clay would be copper. It makes the aroma very strong, yet it completely eliminates flavor. I find the taste quite flat. This clay is only suitable for displaying purposes.
See More Product Information >>
The history of Tokoname is very long back in 12th century. It is one of the oldest 窯 in Japan. However the dawn of Tokoname Clay Tea Pot was around 1800s. Initially the clay used for Tokoname was not 朱泥. In the early stage, the white clay or local 粗土was used in making a Tokoname Tea Pot. The first 朱泥 Tea pot appeared in the year of 1854. It was found that the clay in Tokoname area was very similar to the one produced in Yi Xing area in terms of mineral compositions. By then, Tokoname developed the refining method of clay and successfully introduced 朱砂 Tea pot. In year 1878, Tokoname invited 金士恒 from Yi Xing. He had a significant contribution to the further development of Tokoname tea pot. The Tokoname tea pot has been improved and its design became very refine thanks to his contribution.
日本語サイトへ
