Saturday, March 20, 2010

Types of Clay

There are many types of clay in Japan, all of which have their own character, color and unique aspects. There are six main branches of clay areas in Japan all of which have their own style related to the specific region of where they are from. They include...

Bizen from Okayama Prefecture
Shigaraki from Shiga Prefecture
Seto and Tokoname from Aichi Prefecture (Where my teacher, Arai Sensei is from)

Echizen from Fukui Prefecture

Tamba from Hyogo Prefecture
These six areas are known as the rokkouyo or old kilns of Japan. They have some of the longest histories of ceramics in Japan but they are not the only kilns with such long traditions and steady hold in Japan. There is also...
Mino from Gifu Prefecture

Karatsu, Imari and Arita from Saga Prefecture

Hasami from Nagasaki

Iga from Mie Prefecture

Hagi from Yamaguchi
just to name a few...there are of course many more. But seeing these names of different ceramic types and the names of the areas where they are from doesn't mean much to someone who isn't a pottery fanatic. So I'd like to start with the most basic element to any type of ceramics...the clay!
Understanding what goes into the base material of a piece will help you to understand why each areas colors or textures are the way they are. Of course there are several types of clay in Japan, not to mention unique clays which many potters go into the mountains or woods to find. Today I'll keep it simple, and go off my experience and clays I use at Sara Yama Studio.

There are three basic clays that are always available at Sara Yama, all are from Shiga prefecture.
With the descriptions I've included pictures of what the clays look like wet and fired. Look at the base of the fired pieces to see the clay without color.

The first is Shigaraki 信楽 It is brown in color and has a grainy texture

The second is Koshigaraki 古信楽 It is white and very smooth
Last there is Namigoshi 並漉 It is also brown like the shigaraki clay but is smooth in comparison

To get an idea of the subtle differences look at this shot with all the fired pieces together

Besides these basic three which are always readily available, we can also order specialty clays which have unique colors and sand texture. These clays are usually used by the more advanced members at Sara Yama since from experience they know what texture and color they like best in their pieces.

The most popular is Bizen clay from Okayama Prefecture (Like I mentioned above) This clay is extremely smooth and soft. There is no gritty-ness to it at all and is a wonderful clay to work with on the wheel. It's easy to mold, easy to shave and easy on the hands. It is light brown and when fired turns into a fabulous terra cotta red type color. I love working with Bizen clay a lot, but it has some downsides. Since it is so smooth, it disappears quite quickly when on the wheel. I find myself rinsing my hands often. It is also easy to over water this clay, ie. get too soft, making it difficult to throw without letting it dry again. This is also a very delicate clay, its effortless to make wonderful thin walls but just as easy to have them flop and have to start all over again.

Here is bizen clay in wet and fired form

More types of clay to come! Keep checking back~


  1. Wonderful explanations.
    Feels like a short course.
    Thank You.

  2. youre welcome! i hoped it was well put and easy to understand :)