|Monthly Tech-Tip |
This is a grog clay with 25% Christy Minerals STKO22S grog (20 mesh one size). This piece is about 8 inches tall fired at cone 10R. This body is a Redart, Ball clay base that totally vitrifies to a chocolate brown. But with the added refractory grog it is fairly stable in the kiln and is much more vitreous than other grog bodies. Because it is such a plastic smooth base and because the grog is only one size, this is actually throwable. And it is very resistant to splitting during hand building.
The most common commercially 200 mesh available raw terra cotta clay in North America. It fires red, has low plasticity and matures a low kiln temperatures.
The term vitrified refers to the fired state of a piece of porcelain or stoneware. Vitrified ware has been fired high enough to impart a practical level of strength and durability for the intended purpose.