Volcanic Ash (Pumice)

Volcanic Ash (Pumice) is used in ceramics as a natural source of silica, alumina, and fluxing oxides, making it a versatile additive for both clay bodies and glazes. When added to clay, it reduces shrinkage, improves thermal shock resistance, and creates a lightweight, open structure—ideal for sculptural or insulating applications. In glazes, volcanic ash can act as a natural flux, contributing to smooth, variegated, or speckled surfaces depending on its mineral composition. Because it contains a natural mix of oxides, results can vary, giving unique, earthy textures that reflect its geological origins.

Dust can irritate the respiratory system and eyes due to its fine silica content. Always wear gloves, a dust mask or respirator, and work in a well-ventilated area. Avoid ingestion and wash hands thoroughly after handling.