Expert: Leisha Hiester - 7/15/2010

Question
I've begun experimenting with new product design crafted in ceramic, specifically biscuit/bisque-fired earthenware, and quite like it's textural properties in the unglazed state. The product roughly resembles a deep soup bowl no larger than 12cm in diameter with a wall thickness of about 3mm.

My question would be, how does biscuit earthenware compare with other ceramics in terms of toughness when dropped? Would a similar piece in stoneware, porcelain or another ceramic better withstand impact? Please describe their strength. Is their an additive used to produce a more resilient ceramic?

Thank you!
Silas

Answer
Silas,
Congratulations for experimenting! I applaud your efforts so much. That is exactly how great art is often achieved.

Your instincts are right, stoneware and porcelain are a bit stronger than earthenware. That's exactly why they're used for dishes. Are you looking to drop your dishes?

Yes, there are additives, fibers and more you can mix in with your clay to strengthen it. Here's one suppliers site with some invaluable information for you.

http://www.sheffield-pottery.com/Raw_Materials_Dictionary_Glaze_making_Clay_Ingr...

If you have a local supplier, they should be able to supply you with an additive.

Hope this helps,

Leisha