Hard, dense firebrick generally used only in high-stress areas of kiln (floor, burner ports, flues, bag wall) and for corrosive firing processes (salt, soda, wood).
Source: Clay: A Studio Handbook
Hard, dense firebrick generally used only in high-stress areas of kiln (floor, burner ports, flues, bag wall) and for corrosive firing processes (salt, soda, wood).
Source: Clay: A Studio Handbook