This melt fluidity comparison demonstrates how similar the substitute L3617 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). This substitute is chemically equivalent to what we feel is the best average for the chemistry of Cornwall Stone.
Substituting Cornwall Stone
Calculating a recipe of materials having the same oxide chemistry as Cornwall Stone
A Low Cost Tester of Glaze Melt Fluidity
This device to measure glaze melt fluidity helps you better understand your glazes and materials and solve all sorts of problems.
Material substitutions in ceramic glaze and body recipes must consider their chemistry, mineralogy and physical properties