Glasuuritud

Glasuuritud is an Estonian term used to describe ceramics or pottery that has been coated with glaze and fired, yielding a glass-like, vitreous surface. The glaze is a silicate-based coating containing fluxes and colorants that, when heated to high temperatures, melts and fuses with the ceramic body.

The process typically begins with a solid ceramic body that is bisque-fired to a stable state. The glaze is prepared as a suspension or paste and applied by dipping, brushing, pouring, or spraying. After application, the piece dries and is fired in a kiln to a temperature appropriate for the glaze and body, often corresponding to cone 04–10 depending on the materials. During firing, the glaze melts and forms a continuous glassy layer.

Glazes vary in appearance and function. Transparent glazes let the body color show through; opaque glazes obscure it. Finishes can be glossy or matte; crackle patterns (craquelé) can occur by design or due to thermal stress. Colorants such as cobalt, copper, manganese, or iron produce blues, greens, reds, and browns. Some glazes are crystalline or can be decorative with engobes.

Glazing has ancient origins in many cultures; glaze chemistry and techniques developed in Mesopotamia and China, then spread to Europe and elsewhere. In Estonian ceramics, glasuuritud pieces are common in traditional and contemporary pottery, often associated with tableware and decorative wares.

Safety and sustainability considerations include the shift toward non-toxic glaze formulations in modern practice. Lead-containing glazes have been phased out in many jurisdictions, and proper ventilation and handling are recommended during preparation and firing.