top of page

Raku Firing - the past and the present of the incredible Japanese ceramics technique

Updated: Nov 23, 2021

Raku ware (楽焼, raku-yaki) is a type of Japanese pottery traditionally found in tea ceremonies. An attentive eye can recognize raku-fired pottery by its lead glazes, hand-shaped, and relatively porous clay body. These characteristics result from low firing temperatures and the removal of pieces from the kiln, a type of oven used by ceramists, while still red/orange hot.

Raku fired wares are intrinsically linked to the Japanese philosophical concept of Wabi-Sabi and Zen Buddhism. Its rise marked a critical point in the historical evolution of Japanese ceramics.

Michael Lancaster and Barbara Harnack, husband and wife artist team and founders of Calliope Art and Craft Gallery, have been firing Western-style raku together since 1980.

In this article series, Michael covers the rich history of Japanese and American Raku and the profound connection with the tea ceremony in Japan. In the second part, he shares his secrets about their Raku style and materials used.

Raku Fired Ceramics
"Button Hole" Raku fired piece by Barbara Harnack

Raku 楽: the origin

The term Raku is derived from the Kanji character meaning "enjoyment" or "ease." For fifteen generations, it has been the title and seal used by a dynasty of potters whose work established the oldest tradition of Japanese raku (make a clay bowl -

Tanaka Chōjirō (長次郎) (1516-?1592), the father of Raku, is a figure still shrouded in mystery. All we know for sure is that he was not Japanese, probably originally from Korea or China.

There are two plausible stories of how he arrived in Japan: Toyotomi Hideyoshi, also known as the second "Great Unifier" of Japan (Toyotomi Hideyoshi - Wikipedia), dreamed of conquering China. He needed to cross through Korea first to accomplish his vision. When Hideyoshi received refusals to his demands by Korea to travel through the country, he instead invaded Korea. Chōjirō could have been captured during the war and brought back to Japan. According to other traditions, he was the son of one Ameya, who is said to have emigrated to Japan from Korea or mainland China.

Historical evidence shows he was a potter, and he was called to replace the broken tiles roof of Toyotomi Hideyoshi's Jurakudai palace in 1574.

All the ridge tiles needed to be handmade; Chōjirō came up with the clever idea of building a Kiln on-site to fire new tiles promptly to replace the broken ones.

He came up with a novel technique of firing and cooling these tiles in a matter of a few hours. He created what potters call an "open clay body", a mixture of clay that can take rapid expansion and contraction. He brought the temperature up quickly in the kiln and then pulled the piece out to cool it. It is fascinating for the history of Raku to see how Chōjirō cooled the tiles. He used rice husks to create a small fire that was cooler than the tiles; therefore, it would hold the heat around while the tiles rapidly cool underneath, slowing the process down.

His work pleased Toyotomi Hideyoshi, Chōjirō's successor received a golden emblem with the kanji character for raku 楽, which officially established the Raku dynasty of potters.

The current Raku grandmaster is Kichizaemon XV, and he is still a direct descendant of Chōjirō and his lineage (Raku History).

Wabi-sabi and Raku Ware

Wabi-sabi(侘寂) is a Japanese philosophy concept centered on accepting transience and appreciating imperfection as beauty.

Many aspects of Japan embrace this view. From products of art to Japanese architecture and tea ceremony, a central function in the Japanese culture.

In the later Muromachi period (1336 to 1573), the drinking of green tea was a festive gathering enjoyed mainly by the Japanese upper-class, with a predilection for expensive wares of Chinese origin known.

As Zen Buddhism from China sprouted in Japan, a new style of Japanese tea ceremony, known today as Wabi-cha (わび茶; 侘茶; 侘び茶) emerged. Wabi-cha matured as part of a movement to honor local wares and more sober styles (Wabi-cha - Wikipedia).

Zen tea master Sen no Rikyū, a pioneer of this movement, commissioned Chōjirō to produce wares that embodied Wabi-cha's tea philosophy. The result was monochrome black or red tea bowls empty of any decoration -to harmonize with the values of simplicity, austerity, and quiet appreciation of Zen Buddhism.

The shape of a raku bowl is simple: a wide, straight-sided vessel set on a narrow base and molded solely by hand. The uniqueness of each piece represented an attempt to enter a new concept of beauty by deliberately repudiating the traditional idea of perfection as beauty.

Meiji Restoration

Two polarised aesthetic traditions characterize Japanese pottery. On one side, there is a tradition of simple pottery, mostly in earthenware, which embodies the aesthetic principles of Wabi-sabi and is often associated with Zen Buddhism - most Japanese raku ware fits this category. The other tradition aligns with highly decorated and brightly colored factory wares, influenced mainly by China and Western ideals and highly demanded in Europe.

During the Meiji Restoration (1868-1890), Japan opened up with the Western world after nearly 300 years of almost complete isolation. The government, aware of the economic benefits of cross-cultural pollination, encouraged Japanese artists to study abroad, expose themselves to Western standards; and invited Western artists to teach in Japan. While Japanese artists kept looking for inspiration in the East, they also began adopting Western styles into their designs.

A typical vase of Meiji period production is a highly decorated porcelain that combines both East and West stylistic influences.

By the end of the nineteenth century, arts were thriving in Japan; artisans found their crafts becoming very popular in Europe and America.

International fairs like the Paris Exposition of 1867, the Philadelphia 1876 Exhibition, and the Chicago World Fair of 1893 played a fundamental role in promoting Meiji-period ceramics to an international audience (Interior Design and Decorative Arts, Meiji Restoration, Japan).

American Raku

In 1911 Bernard Leach, experienced ceramics for the first time at a party in Tokyo that held a traditional tea ceremony and Raku firing - He was invited to decorate a piece fired before his eyes in a portable raku kiln. The art of pottery-making bewitched him. Although he continued to experiment with Raku firing for a few years following his return to England in 1920, western artists largely forgot this technique after the 1930s (Raku ware - Wikipedia).

Raku's unpredictable results and intense color began attracting modern potters again in the late 1950s. Hal Riegger and Paul Soldner are considered the pioneers of this new Raku tradition, known as American Raku.

Chōjirō never intended Raku to be an art form, but it was a functional style to quickly make something of high spiritual value.

Western raku became art because the process provides a great variety of colors and surface effects, turning into an empty canvas for the skillful potter. These patterns and colors arise from the rapid cooling process and the amount of oxygen allowed to reach the body. American potters still used the traditional Japanese firing process: heating and cooling the pottery quickly, but adapted the second stage of raku firing to form their singular styles. Depending on what outcome the artist aspires to, the pieces are either instantly cooled in water, cooled slowly in the open air, or placed in a barrel filled with combustible material, such as newspaper or husk, which smokes them. Water rapidly cools the pottery, stopping the chemical reactions of the glaze and fixing the colors; the combustible material generates smoke, which blackens the unglazed portions of the pottery. The amount of oxygen released during the firing and cooling process affects the final color of the glaze and the amount of crackle on the surface. (Raku ware | Cerámica Wiki | Fandom.).

Various potters use copper and other metals to bring out a metallic effect. For example, Michael sometimes over-sprays ferric chloride on the surface, a fancy name for iron, to give the sculpture a metallic look. It also lends itself to what he likes to do, making sculptures influenced by the industrial movement.

Post-firing reduction

One characteristic that influences the piece's outcome is the material used in the post-firing reduction, also called smoking: the sculpture is removed from the kiln at bright red heat and placed in containers of combustible materials. A well-known Raku artist and a dear friend of Harnack and Lancaster fires inside his studios. He has a wall of fans to get the smoke out, but despite the excellent aeration, he burned everything down. He uses sawdust, which is a highly inflammable material. Raku can be very dangerous.

Chōjirō used rice husk, Barbara and Michael when they were living in upstate New York, used pine needles. Some people use shredded newspaper. Since they moved to Madrid in New Mexico, they have been using dry straw. A potter needs a material that catches fire quickly.

Different materials lead to different results. Each material has a distinct smell and feel. They like straw because they know how the material behaves and therefore have some sort of control over the results.

Barbara Harnack in action

According to Lancaster, “sawdust does not smolder, but the potter needs to dig around it to insert the pieces. I found sawdust annoying and hard to use. It just made all my pieces pure black where it was unglazed”.

People use different materials and they have different preferences based on cost efficiency and the results and the artist’s ability to manage the combustible material. Michael’s advice is to stick to one material and really learn how to use that.

A harmonic Raku firing dance

Michael and Barbara first fired together back in 1979, while she was still studying at Parson's School Of Design. They kept firing Raku sporadically for the following 15 years and then began doing it more full-time in the 1990s.

With every piece of art they made, their style changed and grew, resulting in very untraditional-looking Raku. They use white clay and put a clear glaze over it. The crackle happens where the clear glaze gets the crazing, which is out of their control.

They use stoneware clay but fire it at earthenware temperature. This is part of why it is an 'open clay body.' A raku kiln will typically fire to about 1885°F (1029 °C). Earthenware clay matures between 1740 -1920 °F (950-1047 °C).

Dawn Firing - Michael Lancaster, 2006

On each piece, they apply a layer of underglazes for the colors, and a layer of clear glaze on top, to prevent the smoke from sinking in. Throughout the years, Barbara developed a unique technique to paint with smoke and negative spaces. The clear glaze acts as a sealer for the smoke: when a thin layer of coating is applied, only a thin layer of smoke comes through, which stains the pottery gray; the parts with no glaze color black, resulting from the smoke carbonizing. Barbara is thinking in advance about where the smoke will go and she is painting with the future smoke.

When the kiln reaches about 1850 degrees, it is time for the second act. The duo had melted quite a few thermocouples during their long history of firing, so now they rely upon the color inside the kiln, usually bright orange, to establish when the clay is ready. While Michael takes the pieces out using tongs or his special mitts, Barbara adds a handful of dry straw to the metal trash can or the horse trough, depending on the size of the piece. He has to hurry because the intensity of the heat will penetrate through the insulation film of the gloves if he lingers too long.

As soon as each piece is carefully placed in the container, they burn right away. This is the beginning of the cooling and the smoking process. She'll turn around, grab another handful of straw and throw it on top of the Raku piece, before closing the container. While waiting for the process to happen, they start a new dance with the next kiln load.

After about 15 minutes, they open the container again, lift and turn the piece, possibly add some more straw, perhaps not, then close the lid again. That's where painting with the smoke happens. Clay will stain white if they sit in a bed of embers that burn and re-oxidize again. Sometimes they look for that; that's where the control comes in.

Breathing through the mask is uncomfortable, but it safeguards their lungs. Going through the dance is intense. Only after reloading the kiln they can pause, but as soon as the temperature is up, it is time to start again.

“Part of the art of the firing is that we know where we're going and why we're doing it. Why do we move that piece? Why did I pull it back up out of the ashes and add more straw to it? There are many individual processes that we go through, depending on what outcomes we aspire to” (Michael Lancaster).

When the pieces are cool enough to touch, they bring them into the house and scrub away the smoke not infused in the clay. In the process, they use water to clean it all out. The dance concludes with a two days' rest for the Raku ware to dry out, and for Michael and Barbara to finally rest.

“We are extremely focused when we fire; our dance comes from years of the two of us working together. It’s synchronicity. ” (Michael Lancaster).

Relic, Michael Lancaster

2,649 views1 comment

Recent Posts

See All

1 Comment

Oct 13, 2023


bottom of page