Tsuboya ware Tsuboya yaki
Tableware for the masses, produced by Ryukyu’s natural climate
Porcelain masterpieces popular in Okinawa
Tsuboya Ware is a form of pottery produced mainly in Tsuboya, Naha City, Okinawa Prefecture. This is one of the leading examples of Okinawan pottery and is also known as yachimun. The characteristic of Tsuboya Ware is its impressive ceramic decoration using enamel unique to Okinawa. The rich decoration and design of the vessels using various techniques, despite being intended for use by common people, was broadly introduced and made known by Muneyoshi YANAGI, a folk craft pioneer in the Taisho Period.
Tsuboya Ware is split into two types, known as arayachi and jouyachi, and compared to the simple arayachi used mainly for alcohol or water bottles, jouyachi makes separate use of various types of enamel and is baked at a high temperature of 1,200°C. Tsuboya Ware baked in this way has a bulky presence and style, and is renowned as earthenware that reflects the rich natural features of Okinawa. Among the enamels that are used, white enamel in particular is characteristic of Tsuboya Ware, where slaked lime and unhulled rice ash are mixed with Okinawa’s gushikami white clay and kina clay, and plays an important role in expressing Tsuboya Ware’s characteristic warmth.
The origin of yachimun in Okinawa is said to derive from the korai roof tiles brought across from Asia during the 14th to 16th Centuries. At this time, the Ryukyu Kingdom enjoyed prosperous trade with China and various countries in Southeast Asia, and it is said that the technology behind the arayachi type of Tsuboya Ware was also conveyed during this period. In the 17th Century, the Ryukyu Kingdom came under the rule of the Satsuma Domain of the Edo Shogunate, and the prosperous trade that had been practiced with foreign countries up to that point disappeared. Accordingly, Sho Nei, the King of Ryukyu at that time, summoned potters from Korea to open kilns, and recommended the production of earthenware actively adopting Korea’s pottery production technology. In this way, jouyachi, which formed the basis of Tsuboya Ware, came to be baked in Okinawa. Finally, in 1682, the Kingdom’s Shuri, Chihana and Wakuta kilns were integrated in the place that is today known as Tsuboya, next to Makishi village, which became the origin of modern-day Tsuboya Ware. Going into the Meiji Period, production of Tsuboya Ware declined for a while, due to the mass-production of cheap earthenware dominating the market. However, in the Taisho Period, it came to receive attention as the folk craft movement gained ground, and finally in 1985 the potter Jiro KINJO was recognized as the first living national treasure in Okinawa Prefecture, and Tsuboya Ware came to be widely known as a traditional handicraft representing Okinawa.
General Production Process
- 1. Excavation of potter’s clay
Red clay (Shimajiri Mahji) and white clay that are peculiar to Okinawa are excavated, and clay is produced at a factory in Onnason. Clay is mixed to suit the type of pottery being produced, and is then filtered and stirred. The clay is then passed through a filter with a pressing machine, the texture of the clay is prepared, and it is then thoroughly kneaded in a kneading machine. In the past, clay kneading was difficult, heavy labor, as all work was carried out by hand.
- 2. Casting
Lathe casting is used when producing containers or vases. There are electric lathes and foot-controlled kick lathes. Portable Okinawan liquor containers, portable sake jugs and small Okinawan lion statues are also produced using molds. Large Okinawan lion statues are produced by the technique of forming by hand, which makes it possible to produce statues that each have different facial expressions. The method of casting with a wooden model is used when producing zushigame jugs, which in olden times were used in Okinawa to carry ashes of the deceased.
- 3. Engobing
After casting and drying, engobe known as nabu is applied to cover the surface of the red clay. Nabu uses gushitou white clay, which is unique to Tsuboya Ware, dissolved in water. The engobing process is called jiigakii, and it produces a white color with a gentle texture and thickness that is characteristic of Tsuboya Ware.
- 4. Decoration
After applying enamel, decoration - the most valuable aspect of Tsuboya Ware - is performed. While enamel is half-dried, line-engraving is carried out on the unglazed pottery. Various techniques can be used, such as applying fillings to give thickness similar to that of engraving. The main characteristic of Tsuboya Ware is its boldly carved patterning on the unglazed pottery. Red painting is also applied after glost firing. Tsuboya Ware is red in color and particularly prized as a first-class article.
- 5. Overglazing (with enamel)
Finally, the earthenware is given lustre by overglazing with enamel. Overglaze also uses raw materials that are typical of Okinawa, such as coral limestone and rice husks. There are also various colors of overglaze that are used according to the design of the pottery being produced, such as shirogusui (transparent glaze) using white clay, amber akagua, and blackish kurogusui.
- 6. Firing
Firing, which is the final process in earthenware production, is normally carried out twice, but for Tsuboya Ware firing is carried out only once after finishing the process up to decoration. This is important work, as once the fire is lit it will continue to burn for at least 10 hours without stopping. In times gone by, firing was carried out in traditional climbing kilns by burning firewood, but due to the development of residential areas around Tsuboya and problems regarding smoke pollution, the use of firewood kilns in Tsuboya has been restricted. Today, gas kilns are used for firing in Tsuboya. The advantage of a gas kiln is that it is easy to control temperature and produce uniform quality. Since potters dedicated to the use of firewood kilns have moved their kilns to the village of Yomitan, the traditions of Tsuboya Ware have been continued in the production of earthenware there as well.