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Sort of. This supplier web page quotes them for each clay body. And you can calculate the coefficient of thermal expansion for a glaze (as shown on the right in Insight-live). Can we say that this glaze with a calculated COE of 7.0 is thus compatible with this body having a measured COE of 6.99? No. Manufacturers intend the COE numbers for comparison. On a body having a low COE glazes will craze more and shiver less and on one having a higher COE they will craze less and shiver more. Glazes are the opposite, low COE glazes craze less (and vice versa). Thus a body having a COE of 6 will craze glazes more than one measuring 7.0. But whether it fits a specific glaze is something that can only be determined by testing.
| Glossary |
Calculated Thermal Expansion
The thermal expansion of a glaze can be predicted (relatively) and adjusted using simple glaze chemistry. Body expansion cannot be calculated. |
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