What are the components of Don's Rutile glaze?

1the glaze

Don's Rutile is a famous stoneware glaze — potters love it for its buttery, mottled, honey-and-cream surface.

2five ingredients

Underneath that beautiful surface, it's really just five dry powders, weighed out by percentage and mixed with water.

3feldspar · flux

Custer feldspar is the main flux — it melts in the kiln fire and turns the powder into glass.

4silica · glass

Silica is pure ground glass-former — without it the melt would be too runny and thin to hold its shape.

5gerstley borate

Gerstley borate is a second, lower-temperature flux — it helps the glaze melt smoothly and evenly at cone 6 or 10.

6kaolin · clay

Kaolin, a pure white clay, keeps the glaze suspended in the bucket and stops it from sliding off the pot.

7rutile · colorant

And the star — rutile, a titanium-bearing mineral — is what breaks the glaze into that golden, cratered, mottled pattern.