The strange vitrification profile of a talc body

Thursday 13th June 2013

This body is made from approximately 50:45:2:3 insight-live.com/material/80">ball clay:talc:whiting:bentonite. These SHAB test bars are fired from cone 2 to 9 oxidation and 10 Reduction (bottom to top). From them the porosity and fired shrinkage can be measured (the SHAB test). Notice that the fired shrinkage is pretty stable from cone 2 to 8, but accelerates at cone 9 oxidation. But in reduction this stage has not been reached yet. The same thing happens with porosity, the cone 9 bar is dramatically more dense than the cone 8 one. But in reduction, it is still porous.

Pages that reference this post in the Digitalfire Reference Library:

Talc, A terra cotta clay fired from cone 06 (bottom) to 4, Reduction Firing, Vitrification, Artware

This post is one of thousands found in the Digitalfire Reference Database. Most are part of a timeline maintained by Tony Hansen. You can search that timeline on the home page of digitalfire.com.