Shodai ware

Shodai ware Shodai yaki

400 years of history:
simple but strong and bold pottery

Description

What is Shodai ware ?

Shodai ware (called Shodai yaki in Japanese) is a form of pottery baked mainly in the northern part of Kumamoto prefecture.
This craft is distinguishable because of its simple texture, strong form, and bold design, which is due to the pouring method of applying enamel. Shodai clay with high iron content is used as the potter's clay, which is covered with dark reddish-brown enamel, but its characteristic design is produced by pouring differently colored enamels like yellow and white. These are produced from the ash of straw or bamboo grass. There are three color groups depending on differences in the mixture of enamel: blue, yellow, and white. Shodai ware has also been called gotoku-yaki, which means "five virtues", because it does not corrode, does not transmit odor, is protected from moisture, has antibacterial effects, and a long life span. This is why Shodai ware has become popular not only for tea utensils, but also as practical tableware for daily use.

History

Shodai ware is said to have started in 1632, when Tadatoshi HOSOKAWA, head of the Hosokawa clan, took up a new post alongside potters Genshichi and Hachizaemon. He started baking earthenware in a kiln opened at the base of Mt. Shotai. As the official kiln of the clan, it used to serve for baking items for daily use which were mainly tea utensils and hibachi (earthenware indoor heating pot). Then, due to the domain's policy of promoting industry as well as the backing of the Hosokawa family, the Senoue kiln was established in 1836 by Rin-emon SENOUE, a government administrator. As a result, the number of pottery operations increased and developed as the Shodai ware techniques were inherited. However, as the Meiji period started (1868-1912), the rise of Arita ware and Seto ware led to a period of decline for Shodai ware as the kilns were abandoned in succession. From the Showa period (1926-1989), Chitaro CHIKASHIGE and Heijiro JOJIMA made efforts to revive Shodai ware, and so it returned to the limelight.
Since then, the number of Shodai ware kilns around the base of Mt. Shotai has increased. Today there are twelve locations producing this craft.

General Production Process

  1. 1. Collection of base clay The base clay is collected from clay beds around Mt. Shotai in the city of Arao, Kumamoto prefecture. Shodai clay contains a large amount of iron and pebbles which produces Shodai ware's characteristic coarseness.
  2. 2. Drying The collected clay is dried outdoors in the sunlight which removes excess alkali and makes it less likely for cracks to develop.
  3. 3. Elutriation The dried clay is ground and stirred with water in an elutriation tank. Then, any deposited debris, grit, or stones are removed and the muddy water is filtered into a separate water tank. The remaining clay is removed and dried under sunlight in a bisque pot.
  4. 4. Storage Once clay has been dried and reached a moderate hardness, it is moved to indoor storage. The pieces are left untouched for a while, incrasing the bacteria inside the clay which results in a finer grain of clay and smooth, soft clay with strong viscosity. If the clay has a fine grain, its rate of shrinkage will become small and cracks will be likely to appear. This craft is easier to produce when there is strong viscosity. Therefore, this step is an important process in the production of ceramics.
  5. 5. Clay kneading Clay is then kneaded thoroughly and moisture is removed from it. There are two clay kneading processes: wedging and chrysanthemum kneading. Firstly, in order to make the softness of the clay even, wedging is done by foot or with a clay kneading machine. This process of kneading the clay, in addition to removing impurities and air bubbles, makes the clay easy to handle and mold on the potter's wheel. Depending on the state of the clay, two types may be kneaded together to compensate for any defects.
    Next, steady chrysanthemum kneading by hand expels air from inside the clay. Because the kneading involves both large rough massaging and smaller careful massaging, the form of the clay ends up resembling a chrysanthemum while it is being kneaded hence its nickname, "chrysanthemum kneading".
    By repeatedly kneading, the clay obtains an even firmness and no air bubbles. This process also makes pieces less likely to scratch and easier to cast.
  6. 6. Casting There are various casting techniques. These include lathe casting, mold press casting using a plaster mold, hand twist casting by hand, slab casting or shaping clay into slabs, and forming into coils.
  7. 7. Finishing the unglazed pottery Once the pottery is partially dried and moderately hard, one to two days after casting, it is finished up. Ornamentation like cutting the base, attaching spouts and handles to teapots, beveling, fretwork, and inlaying is done.
  8. 8. Drying Pieces are dried naturally in the shade so that the moisture is removed slowly. If moisture remains, the pieces will break when firing inside the kiln, and the sudden drying could cause uneven drying, bending, distortion, or the appearance of cracks. It is important to dry the items in an environment with stable humidity and temperature.
  9. 9. Bisque Bisque firing, initial firing before any glaze is applied, is done at 800-900℃ (about 1472-1652℉) for around eight hours. After that, the pieces are left inside the kiln until the temperature cools down naturally. Bisque firing improves enamel application.
  10. 10. Enamel mixing Enamel is the glass-like substance that covers the surfaces of ceramics and porcelain and adds water resistance, luster, color, and patterns. It is produced by mixing clay dissolved in water with ash, finely ground feldspar, or iron-containing ore. The ash is derived from plants like straw, bamboo grass, or hay, or from sources of wood such as various small trees, evergreen oak, Japanese cedar, or pine.
  11. 11. Glazing The enamels used for this craft are charcoal, straw ash, bamboo ash, hay ash, and iron enamel. Subtle differences in the composition of enamel, the temperature, or conditions when firing will produce changes to the color, and there are three different color groupings: blue, yellow, and white Shodai. There are also various glazing techniques that are characteristic of Shodai ware, including dipping, ladling, sprinkling, spouting, coating, slip trailing, bullseye, and double-layer application.
  12. 12. Loading pots into the kiln Pots are loaded into the kiln for firing. Loading requires thorough consideration of potential adhesion between fired containers, ash application, shrinking and softening of clay, the height and placement of containers, and the area around the fire.
  13. 13. Glaze firing While bisque firing was done at around 800-900℃ (about 1472-1652℉), pieces are now baked for around ten hours at a temperature of 1300℃ (2372℉). Depending on the season and weather, the way the kiln burns will be impacted, so it is important to adjust the work to the conditions.
  14. 14. Removal of pots from the kiln After firing, the items are removed from the kiln after they have cooled down. Pieces may break if the kiln lid is opened before the temperature has cooled. It is necessary to wait for around ten hours for the kiln to cool completely.

Where to Buy & More Information

Kumamoto Perfectural Traditional Craft Center

Kumamoto Perfectural Traditional Craft Center Photo:Kumamoto Prefecture

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