A phrase used to describe a pigment's impermanence and tendency to fade or change color under the influence of natural effects such as sunlight. Traditionally a lean layer of size and chalk to form a ground on which to paint. It is used in egg tempera painting and as a coating material. Traditionally used to add color to forms modeled in monochrome opaque paint. To impart a glass-like surface.
Aged glaze is very sensitive to solvents.
The shine, sheen or luster of the surface of a coating. See also sheen. Dirt can be in the varnish, on top of the paint layer, or on top of the varnish. A layer of opaque paint applied to a support to provide a suitable color and texture on which to draw or paint. The dullness of a surface removable by polishing.