Glaze Recipe Scaler

How pottery glaze recipes work:

Glaze recipes are written as percentages that add up to 100. Each ingredient is a percentage of the total dry weight. To make a batch, you decide how much total dry glaze you need, then multiply each ingredient’s percentage by that total.

The formula:

Ingredient weight (g) = Total batch weight (g) × (Ingredient % / 100)

How much dry glaze do you need?

A general rule for dipping glaze: 100 grams of dry glaze (mixed with water to dipping consistency) covers approximately 1 square foot of bisqueware. For brushing glazes, you need about 50% more because multiple coats are required.

Worked example:

A classic cone 6 satin glaze recipe:

• Nepheline syenite: 40%
• Silica (flint): 25%
• Whiting (calcium carbonate): 15%
• EPK kaolin: 10%
• Talc: 10%

You need 500g total for a small batch:

• Nepheline syenite: 500 × 0.40 = 200g
• Silica: 500 × 0.25 = 125g
• Whiting: 500 × 0.15 = 75g
• EPK kaolin: 500 × 0.10 = 50g
• Talc: 500 × 0.10 = 50g

Water ratio: Add 40–50% of the dry weight in water. For 500g dry: add 200–250g water. Mix thoroughly, sieve through an 80-mesh screen, and test consistency — it should coat your finger and drip smoothly.

Colorant additions are calculated OUTSIDE the 100% base:

• Cobalt carbonate (blue): 0.5–2% of dry weight
• Iron oxide (brown/amber): 2–10%
• Copper carbonate (green): 1–5%
• Rutile (tan/brown): 3–8%

For 500g dry glaze with 2% cobalt: 500 × 0.02 = 10g cobalt added on top of the 500g base.

Tips:

• Weigh ingredients on a digital scale accurate to 0.1g
• Always sieve twice for consistent results
• Label every bucket with the recipe name, cone, and date
• Test new recipes on test tiles before glazing finished work