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INSIGHT has been around since 1980 solving materials substitute issues. But it also does many other things.

Try INSIGHT for free

Where to start
in learning glaze chemistry

Digitalfire Corporation makes no guarantees about the information contained herein. It is given as a guide along with support information to help visitors work out the problem themselves.



This site focuses on Gerstley Borate as a boron sourcing material used as a melting agent in ceramic glazes. It has been a foundation material in pottery glaze recipes for years and supplies are gone. Strangely most people have used it without knowing what it really was.

The Best Approach

Most substitutes work in only a few glazes. Conceptually we can substitute GB in any glaze (and even improve it in the process) by calculating a new recipe having the same chemistry and physical working properties but with a different mix of materials (not as difficult as you might think with the right software and technique). The INSIGHT software manual has a chapter in its lessons section on doing exactly this (there is a matching video here). The free download will work for two months before expiring.

Nirvana 1 : With Ceramic Calculations You Don't Need a Substitute!
Nirvana 2 : Improve the glaze while you are at it

Learning From Some Examples

Click here to learn about the substitute the Internet community worked together to create using the above technique. Get the Boraq Recipe, learn about specific glazes (like floating blue, iron reds), what to do if you have problems.

Other Approaches

Laguna Borate, Murray's Borate, Cadycal, Ferro Frit CC298-C, Other Frits, Gillespie Borate, Ulex Empresa Minera, Dal-Tile 439, IMCO, Ulexite, Colemanite

A Learning and Teaching Opportunity

Have we understood our materials? Have we been 'recipe junkies' for too long. There is a great educational opportunity here, why not teach your students about it?

Copyright 2000 Digitalfire Corporation