Crackle Glaze Raku

Crackle glaze raku is a variation of traditional raku pottery firing that incorporates a specific type of glaze known as crackle glaze. In this technique, pottery pieces are coated with crackle glaze before being fired in a raku kiln.

Crackle glaze is a type of glaze that contains materials that cause it to shrink at a different rate than the clay body during firing, resulting in fine cracks or fissures in the glaze surface. These cracks are intentional and create a visually striking effect on the finished pottery piece.

During the firing process, the pottery piece is heated rapidly to high temperatures in the raku kiln. Once the desired temperature is reached, the piece is removed from the kiln while still hot and placed into a container filled with combustible materials, such as sawdust or newspaper. The combustible materials ignite upon contact with the hot pottery, creating a reduction atmosphere inside the container.

As the pottery cools, the reduction atmosphere causes the crackle glaze to absorb carbon from the combustible materials, darkening the cracks and enhancing their visibility. The contrast between the darkened crackle lines and the lighter glaze surface creates a visually striking effect known as crackle glaze raku.