Ceramic Glaze

[Blueberry]

Glaze recipe:
Quartz (for silica)
Schist or gneiss (for alumina)
Feldspar (for flux)
Any pigment

Glaze can be painted onto fired pottery which then needs to be fired a second time to make the new color permanent. Unfired glaze can be washed off with water or by leaving the pottery in the rain.

Edit: The kiln itself can be glazed and requires burning through a full 30 ticks to be fired. Perhaps objects using clay that aren't made with a kiln, like cauldrons, can be glaze fired by building a pyre around them?