Monday, March 14, 2011

A STARTING POINT

When I first started in ceramics back in the days of the alchemists, there was very little to go on if one was determined to make traditionally influenced Japanese style glazes. There were scattered articles and a few books (thank you Nigel Wood, Robert Tichane and Joseph Grebanier) but the place that really got me started was a Ceramics Monthly (2/1977) article entitled; JAPANESE ASH GLAZES by Sasaki Hiroshi. Early on, I used his formulas as the basis for my experiments and with testing, trial & error and altering the formulas; I was able to come up with a nice haiyu ash glaze, a great Oribe, a traditional Shino and a nice Ki-Seto as well.

Please bear in mind, from my perspective these formulas are starting points and after initial testing, you can make judgments as to how to proceed. I also tested most of these glazes between Cone 7 and Cone 10 and also fired them in both neutral and reduction atmosphere. Lastly, once you find a rice straw source to make your ash, it is possible to experiment and come up with a very serviceable nuka-yu glaze.

DOBAI-YU
Wood ash 30 to 50 parts
Feldspar 70 parts

AME-YU
Wood ash 60
Rice straw ash 10
Feldspar 30

BIDORO-YU
Wood ash 40
Feldspar 60
Zinc 5

ORIBE-YU
Wood ash 50
Feldspar 50
Copper ox. 4

KI-SETO-YU
Wood ash 50
Rice straw ash 10
Feldspar 40
Red Iron Ox. 1 to 2%
(a little pinch of CMC in all the glazes helps with adhesion and is recommended)

Illustrated is the interior of a teabowl with an altered bidoro-yu over a Shino glaze. This particular version always produces nice green glass pools on the interior and runny drips (tombo-me) on the exterior.