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Ceramics & GlassFree

Build a Glaze

Design a complete glaze recipe from raw materials. Computes Unity Molecular Formula (UMF), SiO₂:Al₂O₃ ratio, surface prediction, color prediction, food safety analysis, and firing schedule, all in one place.

Recipe Builder

MaterialWeight (g)%

Results

Surface

glossy

SiO₂:Al₂O₃

0

Total

75g

Food Safe

Yes

GlossySatinMatteDry0.00.20.40.60.80123456Al₂O₃ (UMF)SiO₂ (UMF)
Glossy
Satin
Matte
Dry

Add materials to plot on the Stull chart

Color

#e8e4df

Food Safe

No hazardous materials detected

No flux materials — glaze needs at least one flux (whiting, feldspar, frit, etc.)

Tips

1
Start with a preset and adjust. The Stull chart shows where your recipe lands in real-time.
2
SiO₂:Al₂O₃ ratio above 10 = glossy, 6–10 = satin, 3–6 = matte at cone 10
3
Barium-containing glazes are not food safe. The calculator will flag this automatically.

Open formula

Oxide Moles = Σ(material_g × oxide_% / MW)
UMF = Oxide Moles / Total Flux Moles
SiO₂:Al₂O₃ = UMF(SiO₂) / UMF(Al₂O₃)

Converts each raw material’s weight into oxide moles using its analysis and molecular weight, then normalizes by total flux moles (RO + R₂O) to produce the Unity Molecular Formula. Surface texture is predicted from the SiO₂:Al₂O₃ ratio at the target cone range.

Flux oxides include CaO, Na₂O, K₂O, MgO, ZnO, BaO, Li₂O. Surface zones shift between low-fire (≤06–6) and high-fire (8–13). Food safety flags barium and high colorant levels.

Digitalfire / Glazy reference data for material analyses. Stull chart zones from ceramic chemistry literature.

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