With raku pottery, the piece is first bisque fired and is then glazed. In the raku firing process, a special raku kiln is required that reaches temperatures of about 1800°F. In order to complete the firing process, the raku pottery is heated for around 30 minutes. While the raku pottery piece is still glowing hot, it is placed inside a metal can full of combustibles. After the materials inside the metal catch on fire, the can is sealed. The raku pottery is capable of withstanding high temperatures and because it is made from a special type of clay that can withstand thermal shock. As the fire consumes the oxygen within the can, it also draws the oxygen out of the raku pottery and its glaze. It is this process (post fire reduction) stage that creates the unique look of raku pottery. After the raku pottery remains in the sealed metal can for about 15 minutes, it is removed and placed in a can of water. This freezes the patterns that were created during the post fire reduction stage.
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