When making pottery, you usually try to avoid cracks. However, there is a decorative technique where they are desirable: crackle glaze.
To achieve this effect, you use a glaze that shrinks faster than the clay during firing. This creates tension, which leads to cracking. The size of the cracks depends on the type of glaze, the type of clay and the firing temperature.
Be aware that this technique is not suitable for functional pots. Not only do the cracks in the glaze make the pot more fragile than other types of pottery, but they can also harbour all kinds of bacteria. Therefore, only use this technique for decorative pieces!
