For iron glazing (called testu-e in Japanese), designs are painted with pigment containing iron oxide (rusted iron), then coated with a glaze that turns transparent during firing, and fired at a high temperature. This is a basic method of producing decorative ceramics, utilizing the way iron changes colors when fired. When ceramics are painted with the iron oxide pigment, the design appears as painted after firing, but the color can be adjusted to be anything from the original red-black to yellow-brown or pitch black, depending on the temperature of firing and the ingredients of the pigment.
1.The base used for iron glazing is pottery that has been fired once, but is still unglazed.
2.A design is painted on the pottery with iron pigment.
3.The piece is coated with glaze, which is white during application but turns clear from firing.
4.The glaze turns transparent after firing and the pottery is complete. The red areas of the piece are copper pigment.
- "What Are Traditional Crafts? -A Guidebook to Seeing, Learning, and Enjoying-" Edited by the Japan Kogei Association Eastern Branch. Published by Unsodo Reference artworks