brian hall wrote:so what are your thoughts on the fireclay from home depot / lowes?
1. As more Kaolin (Al2 Si2 O5 (OH)4) clay contains as higher is the melting point. Is this true?
2. What about cracking during heating or cooling? How to avoid this? Is this somehow linked to Kaolin content?
3. If higher Kaolin content is better, can I simply mix any found clay with pure Kaolin to make it more heat resistant? Pure Kaolin is not cheap but you can buy it as a white powder.
Jerry Ward wrote:I have some clay that is almost blue looking, what does that mean? When it drys on your clothes it does look whiter
Jerry Ward wrote:Does this mean it is a good choice?
allen lumley wrote: Jerry Ward :Ernie and Erica Wisner report that Blue,blue grey clay contains so universally a very low Alumina Silicate % that it is condemned out of hand. My one conversation
with a potter suggested that the best you should hope for is a terra cotta, If a wet batch feels soapy slippery when handling its the kiss of death ! Not much good news here .