861P
Cone 08 raku firing, about 950°C · Electric or gas kiln, then reduction in a bin · Reduction draws out the metallic flashing and the crackle · Results vary piece to piece with the reduction · Lead-free; not rated non-toxic in the liquid state
$0
A dark red-purple carrying heavy metallic copper flashing.
Spectrum's raku glazes are made for the raku cycle rather than a standard firing. The work fires to cone 08, around 950°C, in either an electric or a gas kiln, and goes into a reduction bin while it is still red hot — either straight out at temperature or after cooling in the kiln to about 870°C, which changes the result. Most of the finished surface is made in the bin rather than the kiln: the starved atmosphere pulls the metal oxides in the glaze back toward metal, which is what produces the copper flashing and the iridescence, and the temperature drop on the way out opens the crackle, which then takes up smoke and reads as a dark web. Because the surface is made by the reduction rather than by a controlled cool, two pieces glazed from the same jar will not come out identical — how long the reduction runs, what is in the bin, and how fast the work is pulled all move the result. It is lead-free. Spectrum does not rate it non-toxic in the liquid state.
