Raku Pottery is strictly for a decorative look. The process of firing the pottery is quite dynamic and has a lot of unpredictability. From a very hot open kiln, you reach in with tongs and pull out a red glowing pot. It cools only a little as you transfer it onto a bed of newspapers, saw dust or some other combustible. Instantly, the flames leap up and start burning the bed. Quickly covering the bed and pottery with a metal garbage can, you hold it down tightly to seal it off from the air. Inside the can, the flames burn vigorously until it uses up the trapped supply of oxygen. If you don’t let oxygen into the can, the flame finds oxygen in the oxides and carbonates of the applied glaze mixture and clay.
The flames attack the pot, stealing the oxygen and transforming the glaze components into a new glaze.
After about 15 minutes remove the hot pot from out of the can and plunge it into cold water. The new glaze suddenly crash cools, hardening in place. Any bare clay would have absorbed carbon from the smoke giving many shades of grey on the piece. You always hope the process doesn’t break your new art piece. The pots created are only decorative and will not hold water unless sealed inside.