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Raw material sources of zinc, lithium, barium, strontium have issues (e.g. precipitates in glaze slurries, toxicity, high drying shrinkage and carbon burnoff that affect laydown and fired surface defects like pinholes, blisters, orange peeling, crystallization). Yet the oxides that these materials supply to the glaze melt - ZnO, Li2O, BaO and SrO, can be sourced from frits which melt much better and remove most of the problems. Consider examples made by Fusion:
-Frit F-493 has 11% Li2O
-F-403 has 35% BaO
-F-581 has 39% SrO
-FZ-16 has 15% ZnO
These frits source other oxides but such are common in most glazes and glaze calculation can be used to retain the overall chemistry. Although these are expensive, the benefits are game changers. But there is a problem: Potters can't get these. Therefore they have difficulty creating the dazzling visual effects of many commercial glazes.
Materials |
Zinc Oxide Raw
|
---|---|
Materials |
Barium Carbonate
A pure source of BaO for ceramic glazes. This is 77% BaO and has an LOI of 23% (lost at CO2 on firing). |
Materials |
Strontium Carbonate
A pure source of SrO for ceramic glazes. It contains 70% SrO and has an LOI of 30% (released as CO2 during firing). |
Materials |
Fusion Frit F-493
This frit is very valuable for one simple reason: It is a higher-quality source of Li2O for glazes than raw lithium carbonate. It contains 11% Li2O. |
Materials |
Fusion Frit F-403
For ceramic glazes this is a higher quality and safer source of BaO than barium carbonate. It contains 35% BaO. |
Materials |
Fusion Frit F-581
A highly quality source of SrO for ceramic glazes than raw strontium carbonate powder. It is 39% SrO. |
Materials |
Fusion Frit FZ-16
The champion in our frit melt-off competitition. This frit showcases the amazing fluxing power of boron and zinc working together. It is 15.5% ZnO. |
Materials |
Lithium Carbonate
A powerful melter very valuable in ceramic glazes. It is 40% Li2O and has an LOI of 60% (lost as CO2 on firing). This material in now incredibly expensive. |
Materials |
Zinc Oxide
A pure source of ZnO for ceramic glazes, it is 100% pure with no LOI. |
Glossary |
Toxicity
Common sense can be applied to the safe use of ceramic materials. The obvious dangers are breathing the dust and inhaling the fumes they produce during firing. Here is a round-up of various materials and their obvious hazards. |
Glossary |
Frit
Frits are used in ceramic glazes for a wide range of reasons. They are man-made glass powders of controlled chemistry with many advantages over raw materials. |
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