Raku is a fast, low-temperature firing in which glazed pieces are lifted from the kiln while glowing hot and often placed in combustible material such as sawdust or paper. The smoke and sudden cooling create crackle, smoke and metallic effects.
What Is Raku?
Raku began in sixteenth-century Japan, where it was used for tea bowls. The Western raku most studios practise today developed in the twentieth century and is quite different: pieces are fired to around 1000 °C in a small kiln, pulled out with tongs, and put into a lidded bin of sawdust or paper to reduce.
The thermal shock and smoke give raku its look: crazed white glazes with black lines, smoky black unglazed clay, and copper glazes that flash red, purple and gold. No two pieces come out alike, which is a big part of the appeal.
Raku clay needs to survive sudden temperature changes, so it usually contains plenty of grog or fire clay. Because it is low fired and smoked, the result is porous and not food safe, so raku is used for decorative pieces.
It also involves fire, heat and smoke, so it is done outdoors with protective gloves, glasses and clothing, usually as a studio workshop with experienced guidance.
This pottery glossary entry from Le Studio Art Space is general educational content. Always follow the clay, glaze and kiln makers’ data for your own materials and equipment.