Which is better for hobby functional ware? Cone 04? Cone 10 reduction?


Friday 15th March 2019

Comparing these two firing ranges and their clays is like comparing apples and oranges. But for hobby pottery, there are some compelling advantages of the insight-live.com/glossary/34">earthenware process (compared to stoneware) that you might not expect. Cone 10R ware is certainly stronger - but only if the glaze fits (crazed glazes dramatically weaken ware). But either one will break if dropped on the floor. The clay of the bamboo colored stoneware mug has a porosity of 2.5%, the clay of the orange earthenware mug has 12%. But the entire base of the orange one is glazed (it was fired on a three-pointed stilt), and the glaze fits well, so there is no point-of-entry for water. The bamboo mug has bare clay exposed on the foot so it will absorb some water. Consider another factor: The bamboo one weighs 432g while the orange one is only 281g. And the orange one will hold 1.92 times its own weight in water while the bamboo one only 1.16! That is because the orange one is made from an artware clay that throws much better - so walls can be squeezed thinner (and many more pieces made from the same amount of clay). The porosity of that clay also makes it a better insulator so it keeps coffee just as warm despite the thinner walls. For hobby potters, the difference in the effort and energy cost needed to glaze these two really favors the artware: It was just a matter of getting out two jars of prepared glaze, brushing on three coats and firing to cone 05 in four hours (while our ability to make the stoneware mug depends on mixing pails of dipping glaze and firings that take almost 24 hours from cold-to-cold).

Pages that reference this post in the Digitalfire Reference Library:

Functional ware at low fire! Don't dismiss it just yet., Artware


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