What’s “Blue and White” pottery and it’s history

“Blue and white pottery” are called “Sometsuke” in Japanese. Pottery and porcelain are decorated under the glaze with a blue pigment, generally cobalt oxide.

The following gallery shows my recent “Sometuke” works.

What is the “Gosu”

The cobalt pigment is one if of the very few that can withstand the highest firing temperatures that are required. Historically, many other colors required over glaze decoration and then a second firing at a lower temperature to fix it. This painting method is called “Uwaetsuke” (Over glaze painting)


The origin of this decorative style was imported from China.  White Chinese  stoneware with their own glazed, white pottery and added decorative motifs in blue glazes.

Blue and white decoration first became widely used in Chinese porcelain the 14th century.

Blue and white ware making is appearance in Japan.   Where it was known as sometsuke. Various forms and decorations were highly influenced by China, but later developed its own forms and styles.

Gosu and how to use of it

A variety of the “Gosu” are available from pottery supplier.  Blue, Black and also various colors of the gosu  is available.  Some of them are come as powder or paste.

In kyoto (Kiyomizu Yaki), a gosu is crushed by the grinding ball mill for a month.

How to use the gosu:                                                                                                              Use the gosu with tapped water or green tea.   Some pro pottery painter prefer using green tea over the water. If green tea is used, make sure that all tea waste are removed.

Green tea contains “tannin” component. This main green tea component will combine with cobalt oxide and become tannin oxide. The tannin oxide will work as adhesive.

How to mix own “Gosu” -Formulation example

Here’s formulation example:

  •  Cobalt oxide    20
  • Nickel oxide    10
  • Manganese dioxide 10
  • Kaolin 50

Please use as reference only and be careful to make at your own risk. The final results are not guaranteed. 

How to practice “Sometuke”  YouTube


How to improve your “Sometsuke” techniques

  • Use quality paint brush, need high quality fine point brush for line drawing (Known as “Kotsugaki”) and “Dami ” brush–a fat brush to paint wide area.
  • Grind gosu well with a mortar and pestle
  • Decorate a lot of works–More you do, become better

Slab Building Gallery | It’s fun to make pottery works with the slab building techniques for the all skill level.

Slub Building Object

With the slab building technique, unique shapes of object could make. Here’s some of my works.

I had a ball making these objects such as “Hina” dolls or small cabins.

Slab Bulding Plate

The slab building technique is also the best method for making simple items such as plate.
The benefit of this method requires only few tools,

If a person knows how to make a slab with cray. Any objects can be make.


Please check my YouTube videos. Over 140 videos show you how to make them.

Note: This software does not allow me to switch multi languages.