Adding an opacifier can produce cutlery marking

Wednesday 2nd April 2014

This is G2934 cone 6 matte (left) with 10% insight-live.com/material/1722">zircon (center), 4% tin oxide (right). Although the base unopacified recipe does not cutlery mark the other two do. Although the marks clean off all of the two on the right, the zircon version (in this case Zircopax) version has the worst and is difficult to clean. Thus, a small change is all that is likely needed. One solution is to reduce the matteness of this glaze, moving to more toward a satin surface. A way to do this is to line-blend in a glossy glaze to create a compromise between the most matteness possible yet a surface that does not mark or stain. Another option is to switch to 400 mesh silica in the recipe, that will enable many more of the particles to go into solution in the melt, thus increasing the gloss a little (an improving the firing surface in other ways).

Pages that reference this post in the Digitalfire Reference Library:

ZrO2, G2934 - Matte Glaze Base for Cone 6, Zircopax, Staining of a sanitaryware glaze after years of use, Opacifier, Cutlery Marking

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.