You are here:

Pottery/Porcelain Firing Information

Advertisement


Question
Dear Ti,
I want to start working with porcelain, however, I need to know the following:
1) how high do I have to bisque fire? Is 1010 degree Celsius  enough or even only 950 degree C as I do with normal clay? Is it the bisque or the glaze that has to be fired to 1260 degree C ?
2) after bisque firing, if I want the peace to remain white, do I have to glaze with transparent glaze or would the peace be shiny or matt without any glaze?
3) If I bisque fire to the maximum of 1260 degree C could I then do a glaze firing with low firing (any colour)glaze which goes to 1070 degree C ?
Your comment would be highly appreciated. Many thanks, Marion

Answer
Dear Marion,

    Thank you for your recent question. Porcelain work is much different than working with earthenware or stoneware. The initial firing is the same as earthenware or stoneware where the ware is fired to cone 05; 1062 degrees C or 1944 degrees F.

    Porcelain requires a matured high fire to achieve the classic ring and translucency to the ware that porcelain is so famous for. Therefore, porcelain must be fire to at least cone 8; 1300 degrees C or 2372 degrees F.

    If you want your piece to remain white, you can use a high fire matte or glossy clear glaze to create the reflective effect you want. Therefore, you will want to use a high fire glaze, cone 10; 1330 degrees C or 2426 degrees F.

    Referencing to question #3, you could bisque fire to cone 05 and use a low fire color glaze to cone 06, however, the porcelain will not have reached maturing temperature and will be brittle and not have the porcelain qualities it is made for. Just to answer a question about high firing the porcelain to bisque cone 10 to reach maturing temperature and then applying a low fire glaze, this would be difficult to do because the pores of the porcelain clay will close too tightly to accept the low fire glaze.

    I was also thinking that you may be wanting to use porcelain because of its whiteness. There are stoneware clays that have a very beautiful white appearance after firing if you are just looking for a white clay. However, if you are wishing to work with porcelain because of its wonderful qualities, then the ideal firing method is to bisque fire to cone 05, apply your high fire porcelain glaze, whether clear or colored and glaze fire to the maturing temperature of the glaze, which is usually cone 10.

    I hope this answers your questions. If you have further questions, please feel free to contact me again. I am always at your service. Much luck to you.

Sincerely,
Ms. Ti Phillips
Earth Stoke 'N Fire Pottery Studio and Artist Retreat
www.earthstokenfire.com

Pottery

All Answers


Answers by Expert:


Ask Experts

Volunteer


Ti Phillips

Expertise

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

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.

Organizations
Alliance of Pottery Artists Worldwide Association

Publications
Ceramic Industry - PPP Wyndstryder Press - Pottery Journal

Education/Credentials
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.

©2016 About.com. All rights reserved.