17 January 2023

The Process of Making Kutani Ware

Kutani ware, while its vivid hues and bold patterns set it apart among Japanese ceramics, is produced through many processes: quarrying, clay making, molding, firing, underglaze painting, and overglaze painting. These processes require a high level of skill and artisans pour their heart and soul into perfecting every single piece. The traditional techniques of Kutani ware have been handed down from generation to generation.

  • Quarrying
  • Clay Making
  • Shaping the Form
  • Bisque-Firing
  • Under glazing
  • Glazing
  • Second Firing
  • Over glazing
  • Overglaze firing 

1. Quarrying

The main raw material for Kutani ware is pottery stone. Today, Kutani ware is made from Hanasaka pottery stones quarried in Komatsu City, Ishikawa Prefecture. Initially, pottery stones from various regions were mined and used to make Kutani ware. However, all other pottery stones besides Hanasaka pottery stones had been mined out and are no longer in use.

Hanasaka pottery stone is characterized by its high iron content, giving the finished clay a rich, grayish-white color. It is also a clay that is easy to shape on a potter's wheel because of its strong consistency.

2. Clay Making

Porcelain pottery is generally made by crushing and refining pottery stones. However, the base material of Kutani ware is made by mixing pottery stones with the clay used in making earthenware. This gives Kutani ware the warm touch of ceramics while retaining the good qualities of porcelain.

3. Shaping the Form

There are various methods of forming the base material. In Kutani ware, wheel throwing and hand-forming are the first two methods. Next are fill-molding, cast-molding, and mold-forming. These are manufacturing methods that primarily utilize molds to create shapes. Since the quality of the product is greatly affected by the quality of the mold, special skills are required to produce them.

Wheel Throwing "Rokuro"

Wheel throwing is a molding method in which a lump of clay is placed on a potter's wheel and spun to form the shape of pottery. This method is used to form various items such as sake cups, tableware, and jars.

Hand-Forming "Tebineri"

Hand-forming is a traditional method of molding a piece of pottery by piling up stringy clay and gluing them together to form a single shape. This manufacturing method brings out an uneven texture that can only be achieved by handmade products.

Fill-Molding "Teokoshi" 

Photo by Miyasou

The traditional method of forming the base of a piece of pottery is fill-molding. In this method, a mold is made for each part of the piece, the clay is pressed into the mold, and then removed from the mold–finally assembling all parts into a single shape. All this work is done by hand. Because of the time and effort required, this method has become the mainstream method for molding pottery such as figurines. 

Cast-Molding "Ikomi"

Photo by KUTANism

In cast molding, casting clay (mud plaster) dissolved in water is poured into a plaster mold instead of the clay used in wheel-thrown molding. This makes it possible to produce products with complex designs. It is also used to mold figurines and tableware, and can be mass-produced.

Mold-Forming "Katauchi"

Mold-forming is a technique in which the base of a piece of pottery formed on the potter's wheel is placed on a mold to reproduce the pattern and shape of the mold. This technique can only be done by hand with a precise process.

First, use a potter's wheel to make the base of a piece of pottery thin, even, and the same size as the mold. If the base of a piece of pottery is uneven, it will crack or break when fired. If it is too thick, it will not be visually appealing, even if it is replicated in a mold. The process of placing the pieces on the mold also requires a certain amount of applied pressure, and the skill of the craftsman must be honed. Because of the skill required, and the time and effort involved, the number of kilns that practice this technique is decreasing nationwide.

However, as long as you have a mold, you can make many of the same ceramics decades or even centuries later. It is quite impressive that you can even revive ceramics from 200 years ago with a 200-year-old mold.

4. Bisque-Firing

Products produced during the molding process are fired at high temperatures and turned into ceramics. Firing takes place after the products have been molded and dried sufficiently. Since ceramics that have just dried are fragile, they are fired at a temperature of around 850°C to make work easier after the first firing. 

5. Under glazing "Shitae"

Photo by CERABO KUTANI

Gosu, a Japanese pigment, is used to paint on the unglazed earthenware. Lines are drawn with a thin brush and painted flat or blurred with a thick brush. This painting technique is generally called Sometsuke. The pigment is reddish brown when applied, but changes to a bright indigo color after the second firing, which takes place after glazing.

6. Glazing

Glaze is a liquid that becomes glassy when fired at high temperatures and forms a film used to cover the pottery. The glaze is applied over unglazed pottery. The work is done quickly so that the glaze is evenly applied over the pottery while being dipped quickly. This process requires a high level of craftsmanship. 

7. Second Firing

The second firing occurs at a high temperature of approximately 1,300°C (2370°F) to 1,400°C (2550°F). The firing time is about 15 to 20 hours. After firing, the kiln must cool down before removing the product. The kilns used for Kutani ware are made of bricks and are fueled by liquefied petroleum gas (LPG) or by electricity. 

 After the second firing, the base becomes white and the glaze becomes transparent and shiny.

8. Over glazing "Uwae" 

Overglaze painting, pleasing to the eye and richly decorative, characterizes Kutani ware. Traditional overglaze paints used in Kutani ware are classified into three types: Japanese overglaze paints, Western overglaze paints, and red overglaze paints. In addition to these paints, precious metals such as gold, silver, and platinum are used to make Kutani ware.

Unlike pigments used for Imari ware and Kyo ware, Japanese pigments for Kutani ware are thickly raised when painted, giving a translucent look. The basic color scheme of Kutani ware is considered to be green, blue, purple, yellow, and red, known as Kutani Gosai, however, many individual Kutani ware makers produce their own unique paints in their ateliers, and the works of famous artists are so unique that they can be recognized by their colors.

9. Overglaze firing 

The pottery is fired at 800-900°C(1472°F - 1652°F) to fix the paints on the pottery.

The light-colored Japanese pigments on the pottery turn vivid after firing. The Japanese pigments turn glassy, giving them a sense of transparency. This allows the underlying Gosu to show through and reveals delicate patterns. This transparency is one of the characteristics of Kutani ware.

In this way, Kutani ware is basically fired three times, although some pieces that have been painted with gold or silver may be fired a fourth time at a different temperature.

Kutani ware is made through a meticulous process. Each and every craftsman carefully completes each step with professional skill. The style of overglaze painting in each kiln during each period differs greatly, making it interesting to compare and enjoy the process. Make a stop in Kanazawa and explore the depth of Kutani ware for yourself! 

Find your favorite Kutani ware 

With its vivid hue and bold pattern, just one piece of the Kutani ware adds a touch of color to the dining table. Please visit our Kutani ware collection page.

Kutani ware Collection

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