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The mug on the left was fired to cone 6 using the PLC6DS drop-and-hold schedule. The one on the right was fired using the drop-and-hold slow-cool C5DHSC schedule. This is the same body, Plainsman M390. The most visible difference is the outside GR6-M glaze, it is turning out a little different at cone 5, firing a lighter less variegated blue. That being said, it sometimes turns out that way at cone 6 also, so there may be other factors. However, a more important difference is the inside glaze, L3500G. Notice how much more glassy and perfect it is. How is it possible to be so much better at cone 5 than cone 6? The slow-cool is the answer, that firing drops at 150F/hr from 2100F to 1400F.
| Recipes |
GR6-M - Ravenscrag Cone 6 Floating Blue
Plainsman Cone 6 Ravenscrag Slip based version of the popular floating blue recipe. |
| Glossary |
Cone 5
Also called "middle temperature" by potters, cone 5 (~2160F/1180C) refers to the low end of the temperature range at which most hobby and pottery stonewares and porcelains are fired. |
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