Pumice, Volcanic Ash
Volcanic Ash is a strong flux and can be used as a color modifier in glazes. Volcanic ash is a unique material to use in glaze formulation that consists of extremely fine particles of volcanic glass that are non-crystalline which imparts unique melting properties on the glaze recipe. As the sources of volcanic ash varies throughout the world, you may notice variations within different batches.
Synonyms: Pumice, Volcanic Ash