Outline of Revealing Glazes

Revealing Glazes

Using the Grid Method

By Ian Currie
Bootstrap Press
Copyright © 2000 by Ian Currie
Click here to read the Copyright Curse
All Rights Reserved
First Edition, June 2000
Soft Cover: ISBN 0 9589275 3 7
Printed in Australia

Every attempt has been made to find the copyright owners of material quoted. If any original source has not been acknowledged, please notify the author so that it can be noted in future editions.

Published by Bootstrap Press



The introduction explores the origins of the grid method and presents some really basic glaze theory including a one-minute chemistry course - all that is necessary to understand the method presented in the book.

  • What is a Glaze?
    • Ian Currie's Blue-in-the-Face Chemistry Course.
    • Raw Materials
  • An Approach to Studying Glazes
    • Origins
    • Some Standards
    • Extending the Range

1. Gradients and Variables

The use of gradients and variables in glaze research and problem solving is outlined. The author shows how to design an experiment so as to reveal hidden cause-and-effect principles. Some basic information on line blending etc. is given.

  • The Holy Grail
  • Isolating Variables
    • Line Blends
    • Biaxial Blends and Quadraxials
    • Blending and Trending - A Puzzle

2. Outline of the Grid Method

This outline refers particularly to the recipe-based standard grid method, the main subject of this book. Much of it applies also to the Seger-based grid method as outlined in Ian Currie's first book: "Stoneware Glazes - A Systematic Approach". Click here to read this chapter in full.

  • The Standard Grid
  • Starting Point
  • Varying Alumina and Silica
  • The Standard Recipe Grid
  • Working out the Flux Material Breakup
  • One Glaze Recipe Explains the Whole Set
  • Colourants and Opacifiers in the Standard Grid
  • Revealing Glaze Principles

3. Choosing a Starting Point

This method shows how to design your own experiment to explore new and exciting areas. This chapter provides a number of methods for designing a set of glazes. Click here to see a sample.

  • Example Sets
    • Glaze C Recipes
  • Rules of Thumb for Choosing a Flux Set
    • Broad Principles
    • Table - List of Flux Materials
    • Advanced Principles
  • Divine Joke
  • Family Set
    • To get Glaze C:
    • Example
    • Developing the Set Further
  • Random Choice

4. Working out the 35 Glaze Recipes

The individual recipes for the 35-glaze grid are easily obtained from the book or from the Calculations Page at this web site. Click here to see a sample.

  • Using the Calculations Page at the web site
  • Using the Flux Breakup Tables
    • The Recipe Table
  • Using the Recipe Grid Diagram
  • Glaze Calculation Software

5. Guided Tour - Colour Plates

For anyone wishing to understand how glazes work, this is the core of the book. Dozens of high quality colour photographs show the different glaze types and show how they are related. Many important glaze principles are illustrated here. Also shown are a number of ways the grid method directs one towards the desired result and better understanding.

  • Isolating Variables
  • Standard Limestone Set (The 0.7 Limestone Set)
  • Corner A Glazes - High Alumina
  • Corner B Glazes - High Alumina and High Silica
  • Corner C Glazes - High Flux
  • Corner D Glazes - High Silica
  • Magnesia Glazes, Strontium Glazes
  • Barium Glazes, Zinc Glazes
  • Feldspathic Glazes
  • Alkaline Glazes
  • Volumetric Addition
  • Clay Body and Firing
  • Using the Grid
  • Family Set
  • Exploring the Limits

6. Preparing, Firing and Assessing a Grid Set

This is the detailed experimental procedure to use in preparing, firing and assessing a grid set of glazes.

  • Glaze Preparation - Volumetric Blending
  • Applying the Glazes to the Grid Tiles
    • Adjusting Water Content
    • ID
    • Layout
    • Glaze Application
    • Tips
    • Applying Colouring Oxides (Optional)
  • Firing the Grid Tiles
    • Firing Type
    • Virtually Identical Firing Conditions
    • Bring out the Differences
  • Assessing the Results
    • Assessing Glaze Fluidity from the Grid Tiles
    • Dealing with Runny Glazes
  • The Next Step
  • Unusable or Dangerous Glazes

7. Volumetric Addition to a Set

This chapter details how the volumetric measuring technique can be extended to gain more in-depth understanding of glazes with minimal work.

  • A new set of glazes with very little effort
  • Method
    • Summary
    • Quantities
    • Addition Procedure

8. Using the Grid Method with Natural Materials

The recipe-based grid method outlined in this book actually arose from a consideration of how to use the grid method with materials whose composition or chemical formula is unknown. Here we see how to introduce unanalysed materials like wood ashes and powdered rock materials into a grid set. Click here to see a sample.

  • Origins
  • Flux Material
    • Wood Ashes
    • Rock and Mineral Materials
  • Alumina Sources
    • Clays
    • Alumina etc.
  • Silica Sources
    • Quartz, Silica, Flint
    • Opal
  • Using Natural Materials in Glaze C


Appendix 1: Equipment and Materials

Appendix 2: Safety and Health

  • My First Glaze - A cautionary tale
  • Legal Obligations
  • Hazards from Raw Materials
  • Non-poisonous Materials
  • Utilitarian Risk
  • Children
  • Occupational Health and Safety Resources

Appendix 3: UsefulMaths and Chemistry

  • Reading a Chemical Formula
    • Some Raw Materials
    • Three Ways to Look at a Glaze
    • Recipe
    • Oxide Weight %
    • Seger Formula
    • Comparing Recipe and Seger Formula for 3 Standard Recipe Grids
    • Reformulating Glazes
    • Chemically Identical Glazes from Different Materials
  • Essential Maths
    • Percentages
    • Percentage Calculation
    • Ratios and Proportions
    • Volumetric Addition to a Set
    • Loss on Ignition - Calcining Calculations
    • Calculating L.O.I.
    • Calcining Calculations
    • The Standard Grid

Appendix 4: The Recipe Table and Flux Breakup Tables

  1. The Recipe Table
  2. Flux Breakup Tables