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Synthetic Cornwall Subsitute

Code: L3617A
Modification Date: 2015-01-26 13:58:55

Custer Feldspar30.030.0%
Pioneer Kaolin12.712.7%
Nepheline Syenite24.524.5%


This demonstrates how you can calculate the chemical equivalent of another material (this was done using Insight software). Cornwall stone is expensive in North America and variable, thus well worth substituting. This blend fires almost identical.

Cornwall Stone off different dates compared to substitute L3617

Cornwall Stone off different dates compared to substitute L3617

This is a cone 11 oxidation melt flow test. Shown (left to right) are the new shipment of Cornwall Stone 2011, the L3617 calculated equivalent (a recipe, see link), the older Cornwall shipment we have been using and the H&G substitute 2011 (far right, mislabelled on the picture). These do not flow well here, a small frit addition is needed to better compare them. However they have melted enough to see some differences in whiteness and degree of melt. Notice the L3617 is more like the old Cornwall than the new Cornwall is.

L3617 Cornwall Stone substitute vs. real Cornwall Stone

L3617 Cornwall Stone substitute vs. real Cornwall Stone

These flow tests demonstrate how similar the substitute recipe (left) is to the real material (right). 20% Frit 3134 has been added to each to enable better melting at cone 5 (they do not flow even at cone 11 without the frit). Links below provide the recipe for the substitute and outline the method of how it was derived using Digitalfire Insight software. This substitute is chemically equivalent to what we feel is the best average for the chemistry of Cornwall Stone.

Out Bound Links

In Bound Links

XML to Paste Into Insight

<?xml version="1.0"?>
<recipes version="1.0" encoding="UTF-8">
<recipe name="Synthetic Cornwall Subsitute" id="98" date="2015-01-26" codenum="L3617A">
<recipeline material="Dolomite" amount="0.600" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Custer Feldspar" amount="30.000" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Wollastonite" amount="2.800" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Pioneer Kaolin" amount="12.700" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Silica" amount="29.500" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Nepheline Syenite" amount="24.500" unitabbr="kg" conversion="1.0000" added="0"/>
<url url="" descrip="Recipe page at"/>

By Tony Hansen

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