Crackle Glazed Matcha Bowl
Inspired by the quiet beauty of Lake Biwa, this handcrafted bowl by Sei Ishido features an intricate network of delicate crackling along the glaze — reminiscent of ice softly fracturing across a winter lake. Each piece is carefully shaped and finished using kan-nyu, a traditional ceramic technique that intentionally creates fine crack-like patterns beneath the glaze.
Kan-nyu occurs naturally when the clay body and glaze cool at different rates during firing, resulting in subtle crazing throughout the surface. Far from a flaw, these patterns are deeply celebrated in Japanese ceramics as a reflection of craftsmanship, imperfection, and the handmade nature of each vessel.
With time and use, the bowl will gradually develop its own unique character as tea gently stains the kan-nyu, deepening the texture and creating organic patterns unique to your piece. In Japanese tea culture, this transformation is cherished — a quiet collaboration between artist, vessel, and owner that evolves over years of use.
No two bowls are exactly alike. Variations in glaze, texture, and crackling are intentional and make each piece truly one of a kind.
Care
- Hand wash only
- Handmade in Japan
- Exclusive to Astrid Tea
Meet the Artisan
Sei Ishido is a ceramic artist based in Kyoto. He spent 12 years honing his skills as a craftsman of Sese ware, a traditional craft of Shiga Prefecture, and after creating works that inherited the spirit of "refined wabi-sabi" of Kobori Enshu, he established his own kiln.
Craftsmanship
The pottery wheel techniques he refined during that time give each of his works intricate forms and unique structures. Many of his works capture the beauty of sunlight reflecting on the water's surface and is inspired by the natural landscape of Lake Biwa.
FAQ
How to Care
Care & Prevention: If you wish to prevent rapid or extreme staining, you can soak the new pottery in rice water (water left over from washing rice) for 15-30 minutes before its first use to fill the pores with starch.
Maintenance: If you want to keep the glaze clean, it is best to rinse the piece immediately after use. Always handwash and dry the bowl right after.
What is Kan-nyu?
Kannyu (貫入) is a Japanese ceramics term that refers to a network of intentional hairline cracks formed on the surface of ceramic glaze.
During the firing process, the clay body and the outer glaze fuse together under high heat. As the pottery cools inside the kiln, both materials shrink. However, the glaze shrinks at a faster, more significant rate than the underlying clay.This difference in shrinkage rates creates severe tension, causing the glassy outer glaze layer to split into thousands of delicate, cosmetic cracks.
Kannyu perfectly embodies the concept of wabi-sabi—finding deep beauty in impermanence, natural randomness, and imperfection. Because the cooling process is unpredictable, no two crackle patterns are ever identical.
Will my bowl stain?
Kannyu is designed to be a porous glaze which means that any tea that settles in the fine lines will darken with time.
The staining is generally considered desirable in Japanese, specifically in wabi-sabi aesthetics, as it adds unique character (a "patina") and reflects the history of use.
Over time, the white or light-colored cracks fill with color, creating a distinct, darker pattern.