The genuine craquelle decor is created by a sufficienttensile stress in the glaze, which causes the glaze cracking during the coolingand creates the required crack-net. When slow cooling of the glazed ware issecured the characteristic crack-net is formed if the difference of the linearthermal expansion coefficient (DTEC) of the body and the glaze is in the rangeof (-36 to -65) x 10-7 K-1. The cracks are so deep thatthey reach the body. The porous ceramic body that is characterised by themoisture expansion is not very suitable for the craquelle. In that case, theformation of cracks continues after cooling and additional thin cracks appear inthe glaze. The results of tests of the crazing glazes showed that the intensityand design of cracks depend on the composition and combination of the glazes,too. Nice and interesting craquelles have been created in the prepared crazingglazes if DTEC (body-crazing glaze) was in the range of (-33 to -46) x 10-7K-1.
