Raku Glazes

Raku ware is a type of Japanese pottery traditionally used in Japanese tea ceremonies, most often in the form of chawan tea bowls. The early technique involved removing glowing hot, carved, clay pieces from a wood-fired kiln and then placing them on the ground to cool. This technique originated in mid 16th century Japan, Raku ware is traditionally shaped by hand rather than thrown, which gives the ware a slightly irregular, rustic shape.

In modern raku, the pottery is fired in a kiln at a relatively low temperature and then moved while still red hot to a closed container. Depending on the desired effect, the pottery is either cooled in water immediately, slowly in the open air, or placed in a barrel filled with combustible material, such as newspaper, covered, and allowed to smoke. Water immediately cools the pottery, stopping the chemical reactions of the glaze and fixing the colours. The combustible material results in smoke, which stains the unglazed portions of the pottery black. The amount of oxygen that is allowed during the firing and cooling process affects the finished result of the glaze and the amount of crackle.

Raku's unpredictable results and intense colours attract modern potters. Generally, copper formula glazes work well for raku (such as the glazes shown below.) The combination of patterns and colours result from the harsh cooling process as well as the amount of oxygen that is allowed to reach the pottery.

For more information, tips and advice on raku, please click on the link below.


Source: Ceramic Arts Network Daily