Since the lunar eclipse I have been busy helping to tend a Cone 10 Reduction Fire. These are always dramatic. Now it is over, and the pieces fired have gone vitreous. This is a good thing. The glazes, however, do not all look as expected. We may not have directed the drafts correctly in the enormous kiln.
A reduction fire uses insuffient oxygen. The carbon monoxide formed unites with oxygen emitted from the clay bodies and glazes, to form carbon dioxide. The formation of carbon dioxide produces color changes in the oxides found in the clay and glazes.
Cone 10 refers to the pyrometric cones used to measure heat inside a kiln. Each cone is made to melt at a different temperature. Cone 10 melts at 2350 degrees, making high fired stoneware, the strongest of clay bodies.
Axé.
coldhearted scientist وداد 