Alkalies are the strong base fluxing oxides of Na2O and K2O. Feldspars are by far the most common alkali sourcing materials, thus the term 'alkali feldspars'. However frits are also an excellent source and sometimes the only alternative to meet the chemistry requirements (e.g. low alumina and high Na2O). Glazes high in these oxides generally are glossy and bright and have high thermal expansions.
Glossary |
Alkaline Earths
Refers to a group of ceramic fluxing oxides that contribute similar properties to fired glazes. They contrast with the alkalis which are stronger fluxes. |
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Oxides | K2O - Potassium Oxide |
Oxides | Na2O - Sodium Oxide, Soda |