Glaze formulation involves a combination of various materials, but four primary ingredients play essential roles in determining the glaze’s composition, appearance, and behavior.
1. Silica:
Silica is the main glass-forming component of glaze. It melts at high temperatures and contributes to the glaze’s overall texture, surface smoothness, and durability.
2. Flux:
Fluxes, such as feldspar or whiting, lower the melting point of glaze ingredients, promoting proper fusion and bonding during firing. Fluxes play a key role in determining the glaze’s stability and viscosity.
3. Alumina:
Alumina, often present in clay or added as alumina hydrate, affects the glaze’s viscosity and maturation temperature. It also contributes to the glaze’s durability and resistance to physical wear.
4. Colorants:
Colorants, including metal oxides and stains, provide the glaze with its desired color and visual character. Different colorants interact with the other ingredients to create a range of hues and effects.
These four main ingredients form the foundation of glaze formulation, allowing ceramic artists to create a wide variety of surface textures, colors, and finishes.