The Microstructure of Some Raw Lead Mat Glazes*

Abstract

This is a report on the microstructure of mats found in the following composition range: These were fired at cones 03, 2, 4, and 6. The compounds present recognized as crystals were anorthite, cession (probably), tridymite, and wollastonite. Willemite was not observed. The good mats were due to crystal separations. A high alumina content was not essential. Anorthite was the principal crystalline form present in mat glazes containing lime.

Effect of soaking time on phase composition and topography and surface microstructure in vitrocrystalline whiteware glazes

“…22 Anorthite, wollastonite, and tridymite were the main crystalline phases present in raw lead matt glazes showing a good quality matt appearance when fired at cones 03, 2, 4, and 6. 21 Despite the drastic changes in firing technology during the past decades, to our knowledge, only little attention has been paid to phase formation in raw leadless glazes as a function of firing parameters.…”

“…Much effort was put in finding satisfactory formulas for raw, good quality matt glazes, and alumina was suggested by many authors as a key factor for causing mattness. [16][17][18][19][20][21] A matted surface finish was reported to be a function of temperature as well as composition. 22 Anorthite, wollastonite, and tridymite were the main crystalline phases present in raw lead matt glazes showing a good quality matt appearance when fired at cones 03, 2, 4, and 6.…”