Yokkaichi's clay is nearly gone, yet it still makes most of Japan's homegrown clay pots. The secret lies in expertly blending domestic and imported minerals.
Earthenware pots, shaped and glazed, lined up at a Ginpo workshop in Yokkaichi, Mie Prefecture. (©Sankei/Maki Tanaka)
As the weather turns colder, hot pot dishes appear on Japanese dining tables more and more often. About 80% of Japan's domestically produced earthenware cooking pots are made from Banko ware, a type of pottery that originated in and around Yokkaichi, Mie Prefecture.
Yokkaichi isn't particularly rich in suitable clay. What turned it into a major production center was its free-spirited atmosphere and pioneering mindset.
Banko ware has a history of roughly 300 years, making it relatively young among traditional crafts. The high-quality clay once found in the area has also been almost completely depleted.
"That's why we source various clays and minerals from Japan and abroad, then blend them ourselves to create our own ceramic clay," explains Seita Kumamoto, 33, executive director of Ginpo, a kiln that has been in business for 94 years. "There's a spirit here of readily adopting good materials, whether or not they're local."
One example is petalite, a mineral from Zimbabwe that is mixed into the clay. During Japan's postwar reconstruction, local manufacturers eagerly adopted this mineral, which improved the heat resistance of their cooking pots.
The region's expertise in blending clay for earthenware cooking pots eventually surpassed that of any other production area in Japan, giving Banko ware an overwhelming share of the domestic market.
Crafted by Hand
Ginpo specializes in heat-resistant ceramics, including earthenware cooking pots. Many of its products have become synonymous with the traditional Japanese hot pot. These classic designs graced countless family meals during the Showa era (1926–1989), and many people will likely recognize them.
To prepare the clay, petalite is blended with several carefully selected clays from different regions, and the mixture is kneaded. Once a vessel has been shaped, excess material is removed and its overall form refined in a process known as bari-tori, or trimming. This stage is performed by hand by specialized craftspeople.
In a workshop filled with the rumble of a clay-kneading machine, Yoko Noda, 45, a shaping artisan with 10 years of experience, was intently trimming a Hana Mishima pot. She pressed a small, specialized knife called a habari against the clay and drew it smoothly along the surface. A thin shaving of excess clay peeled away and fell to the floor.
The process resembles planing wood, but because the surface is curved, it appears to require considerable skill.
"Getting the pressure just right is difficult. It's like peeling an apple: I use centrifugal force to remove the excess in one smooth motion," she explains. "If I stop midway or change speed, the surface becomes uneven. And if I hold the habari at too steep an angle, it catches on the clay and changes the shape."
If too much material is removed or the surface becomes uneven, the work cannot be undone. It is a crucial task that requires the precision of human hands.
Designed for Everyday Life
Once trimming is complete, the pots are coated with glazes in colors developed using the kiln's own blending techniques. They are then fired for 24 hours in a huge tunnel kiln, with the temperature carefully maintained just below 1,200°C.
As a cooking vessel, earthenware retains heat well, helping ingredients soften and bringing out their natural sweetness. As a serving vessel, it has a strong visual presence without being overpowering, fitting naturally onto the family table without distracting from the food.
Practical and versatile, it is nevertheless so closely associated with winter that it often gets tucked away at the back of the cupboard during spring and summer.
"I want to make earthenware pots into tools people can use 365 days a year," Kumamoto says.
To achieve this goal, he founded his own company and is developing Petari, a brand of heat-resistant ceramics based on the principles of traditional earthenware cooking pots but designed to offer more than the conventional hot pot. In September this year, the brand launched a small, straight-sided pot.
An Evolving Craft
Kumamoto, who is also a craftsperson himself, led an extensive design process to combine earthenware's superior heat retention with a contemporary aesthetic rarely seen in traditional hot pots. The team reportedly produced more than 10 prototypes of the handles alone.
"If Petari can create a new category of versatile, multipurpose heat-resistant ceramics, Banko ware won't stagnate," he says. "Instead, the entire production region will be able to create things with greater freedom and creativity. That's the future I want to help build."
The brand name is derived from petalite, the mineral used in the clay.
(Read the article in Japanese.)
Author: Maki Tanaka, The Sankei Shimbun