I could not figure out why our glazes were looking so flat and dead until I read about gerstley substitutes not being at all the same as what Gerstley is. Has anyone come up with glazes that don't use Gerstley but that still give depth and life to the cone 6 oxidation glaze firing? We were using glazes called Toby's Red (high in GB and Iron), Honey (high in GB with rutile, floating blue and Erins white. All are now giving us lack of depth, running, and crawling. Any suggestions or recipes are appreciated. DKat
Gerstley Borate - has anyone come up with a GOOD replacement
Nov 13, 2003
4 Replies
If the amount of gerstley isn't too high you should be able to reformulate them with a frit like Ferro 3134 or 3124. You can't make a direct substitution though and will have to run the original recipe through a program like Insight or Matrix to get the molecular formula and then match it using a frit. Boraq is supposed to be a pretty good substitute. Some of the substitutes work on some glazes but not others. I have some cone 6 glazes with pictures and recipes on my web site if you'd like to take a peek.
Regards, June
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they have a substitute for gertsleys borate called murrays borate its a near 1 for 1 match. "Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin, 1759
You might find
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Also, you can still buy gertstley borate. See the materialsin the store at
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Which GB substitutes are you using? I've been using Gillespie Borate but can't compare with the original GB because I'm too new to all this stuff... the old GB went out before I came in!
Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis
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