A limit or target glaze formula. What does this mean?


Wednesday 11th May 2016

Recipes show us the materials in a glaze but formulas list oxide molecules and their comparative quantities. Oxides construct the fired glass. The kiln de-constructs ceramic materials to get the oxides, discards the carbon, sulfur, etc. and builds the glass from the rest. You can view glazes as recipes-of-materials or as formulas-of-oxides. Why use formulas? Because there is a direct relationship between the properties a fired glaze has (e.g. melting range, gloss, thermal expansion, hardness, durability, color response, etc) and the oxides it contains (links between firing and recipe are much less direct). There are 8-10 oxides to know about (vs. hundreds of materials). From the formula viewpoint materials are sources-of-oxides. While there are other factors besides pure chemistry that determine how a glaze fires, none is as important. Insight-live automatically shows you the formulas of your recipes and enables comparing them side-by-side. Click the "Target Formula" link (on this post at digitalfire.com) to see what each oxide does.

Pages that reference this post in the Digitalfire Reference Database:

Creating Your Own Budget Glaze, Digitalfire Insight-Live, Analysis, Target Formula, Limit Formula, Formula, Oxide


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.