glaze (in pottery)
glaze, translucent layer that coats pottery to give the surface a finish or afford a ground for decorative painting. Glazes—transparent, white, or colored—are fired on the clay. Of the various artificial mixtures used for glazes, that for whiteware contains borax and lead, whereas a salt glaze is used for stoneware. No lead is used for porcelain. The coloring agents are oxides of different metals. In the 16th and 17th cent. glazes were also used in painting to enhance the luminosity of oil or tempera colors. Titian and Rembrandt were especially adept at glazing techniques.