Warning:

The unpredictable outcome of this process makes it addicting.

After a piece is painted with specially formatted glaze it is placed into a gas kiln.  The kiln is heated up to between 1600 and 1800 degrees.  At this point, the piece is removed from the kiln and placed into a reduction chamber filled with combustible material (newspaper, straw, sawdust, etc.)  The reduction chamber is covered for about 15 - 20 minutes, then the piece removed and dipped into water. 

Due to thermal shock, the piece may crack and break apart.

Almost any low-fired glaze can be used for this process, but the specially formatted glaze recipes produce more of a "cracked" appearance which take on a darker color from the carbon in the reduction chamber.