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Pottery/Bubbling on Glazed Pottery


My granddaughter and I recently took a ceramic class.  We made slab characters.  They were then glazed and fired--glaze over greenware.  Her figure glazed well, mine bubbled.  Same glazes used.
Can I have mine re-fired?  Why did they react differently in the kiln?

Dear Karen,

    Thank you for your recent question. Although the same firing method was used for the slap pieces, rarely, but possible can the glaze react differently due to the location in the kiln. The bubbling resulted from underfiring. Bubbles happen when a glaze is in its melting stages and gasses are released. If the slab is located in a kiln where the elements are not reaching temperature, the glaze does not have a chance to release all of the gasses, resulting in bubbles being caught up in the melt and frozen in time.

    First, let your instructor know that the glaze was fired with another piece that fired correctly, when yours did not. Let them know that they may need to check the elements on the kiln to insure they are not wearing out and failing to reach maturing temperature.

    Next, let your instructor refire your piece to maturing cone. If the kiln reaches maturing temperature, your piece should turn out fine.

    I hope this helps you. If you have further questions, please feel free to contact me at any time. Always at your service. Good luck!

Ms. Ti Phillips
Earth Stoke 'N Fire Pottery Studio and Artist Retreat


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Ti Phillips


Will answer any questions on hand building, wheel, glaze, firing. Speciality questions to include those in glaze calculation and development, firing techniques. Please do not send questions on identifying pottery. Although I would love to add this to my question topics, I have a retreat to run as well as the studio and volunteering on AllExperts, and therefore do not have the available time to research indentification and marks. Thank you for understanding.


Experience includes 30 years in pottery design and education. Have taught online and studio classes worldwide for the last 20 years. Own a pottery retreat specializing in firing techniques. Have 12 years solid experience in glaze calculation and formulation as well as problem solving in glaze chemistry. I am the first potter in the United States to have developed a complete package of pottery equipment blueprints for a studio. The blueprints include wheels, kilns, studio furniture, wedgeboards, raku kilns, slab rollers, ball mills and studio tools.

Alliance of Pottery Artists Worldwide Association

Ceramic Industry - PPP Wyndstryder Press - Pottery Journal

University of Sciences and Art's of Oklahoma, studied under Professor Jaymes Dudding.

Awards and Honors
Potter of the year with APAWA, various awards for showmanship and design.

Past/Present Clients
Available upon request.

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