Still today, in Japan raku ceramics are highly valued and many of these creations are real works of art. The irregularity of the raku object is one of its fundamental characteristics as well as the particularity of the iridescent color and unique reflections.
To acquire these characteristics, the incandescent object is extracted, temperature is about 1000°, undergoing a thermal shock, and immediately immersed in wood shavings and dry leaves or paper. The contact with these materials causes the ignition of flames, these give iridescent colors and metallic reflections. This process is called reduction. A total reduction gives a black color and, depending on the amount of residual oxygen, color varies on a gray or brown scale. The peculiarity of this process is that each and every single object remains unrepeatable, its shape and its color are often anarchic and unexpected.