Sovereignty Module: Mix the Melt

Complete Glaze Chemistry: From Raw Materials to Formulated Glazes

Glaze chemistry empowers the potter to create, modify, and troubleshoot glazes from raw materials. This campaign covers glaze structure, unity formula, material substitution, and testing methodology.

Chapter 1: Glaze Structure

Chapter 2: Unity Molecular Formula (UMF)

The UMF expresses a glaze as molecular ratios: 1) Fluxes (RO/R2O) are set to total 1.0. 2) Alumina (Al2O3) is expressed as a ratio to fluxes. 3) Silica (SiO2) is expressed as a ratio to fluxes. 4) This allows comparison between any two glazes regardless of recipe format.

Chapter 3: Common Glaze Materials

Chapter 4: Colorants

Chapter 5: Testing Methodology

Reference Card

1. Silica is the glass (every glaze is fundamentally melted silica; all other materials serve to modify the melting temperature, surface quality, and color of this glass). 2. Alumina prevents running (without alumina, glaze flows off vertical surfaces; alumina stiffens the melt, keeping the glaze where it is applied; kaolin is the primary alumina source). 3. Fluxes lower the melting point (pure silica melts at 3100°F; fluxes lower this to practical kiln temperatures; different fluxes produce different surface qualities). 4. The UMF enables comparison (a recipe in grams tells you nothing about glaze chemistry; the UMF reveals the molecular relationships that determine how a glaze behaves). 5. Test systematically (changing multiple variables simultaneously makes it impossible to know which change caused the result; change one variable at a time in controlled tests). 6. Keep detailed records (every test tile must be labeled with the recipe, clay body, firing temperature, and atmosphere; without records, successful results cannot be reproduced). 7. Glaze chemistry is the potter's deepest knowledge (understanding why a glaze behaves as it does, rather than just following recipes, gives the potter the power to create new glazes and solve problems). 8. The interaction of fire and chemistry creates beauty (the colors and surfaces of pottery glazes emerge from chemical reactions at extreme temperatures; this alchemy of earth and fire is the heart of the ceramic arts).