|Monthly Tech-Tip |
These test bars are fired from cone 10 reduction (top) and 10 oxidation down to 6 oxidation. The drying shrinkage and the fired porosity and shrinkage are shown on the chart. This is a refractory clay, even at cone 10. It has excellent plasticity, similar to a typical throwing pottery clay. This can do at cone 10 what Redart does at low fire: Be added to a white burning clay body and turn it red. But 75% or more Redart is needed while as little as 25% if this can make a body red. While Redart is not plastic enough to use alone, this is (so it will have minimal impact on the drying and plasticity of the body). Since C-Red is refractory it will reduce the maturity of vitreous cone 6 bodies. But that is good because achieving red coloration at stoneware temperatures depends on a body not being vitreous (vitrification turns the color to brown). We tried adding only 30% of this to M370 porcelain, that produced a deep red stoneware.
Industrial Minerals Co website