Also called kaeragi or kairage. It is a chink in the glaze. In Korean well tea bowls, the glaze is often seen as sharkskin around the waist and the base of the bowl, and is admired as a scenic feature. Kairagi was originally the skin of a butterfly shark used for swords, and is called kairagi because of its similarity to sharkskin in the way the glaze is wrinkled and rough. Rough ceramics are undercooked, so the glaze does not adhere sufficiently, resulting in kairagi, which can be regarded as a technical defect. (The Complete Catalogue of Pottery)
