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thermal shock/microwave

updated mon 30 jun 97


Cummings Pottery on mon 9 jun 97

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Have you considered the possibility that your customers may have heated
liquids in the mug in a microwave? It is my understanding that
microwaving will heat the metallic elements in the glaze and/or the clay
at different rates creating stresses. I have always advised customers
against microwaving my pottery, just oven and dishwasher safe. Any
comments or experiences will be appreciated.
Marilyn Price
I have been microwaving my pottery for years. I am always nuking my coffee
mug during the day. Never had a problem, either with my highfire or lowfire?
As a matter of fact, that is one of the virtues I extol to my customers.
Could your thermal expansion problem and cracking have to do with
black-core? Break open a pot and see if the clay looks "burnt" inside. I
use to love to reduce the heck out of my saltkiln (flames!!!!!!), until I
realized my teapots were cracking when folks poured in hot water. Pat