The technique is called raku, an old Japanese tradition.
The ceramic pieces are painted with glaze and fired in the oven known as a kiln. Instead of cooling down in the kiln as what typically occurs, the pieces are removed while still glowing hot and placed in a container filled with combustible material for a short time. This is known as reduction firing. Eventually, all of the available oxygen is used. This then draws oxygen from the glaze and the clay to allow the reaction to continue.
It is raku's unpredictable results and intense color that attract modern potters. In a normal setting, the students know the exact colors that their pieces will be when they come out of the kiln. In the raku method, cracking of the colors occur and often a metallic look is achieved.
"It's spontaneous," said teacher Elizabeth Whyte. "What happens, happens."
Netten has been sharing the techniques with the current art teachers for the last couple years. He is sure that they will soon be able to teach the technique on their own.