Seaweed Traces Shiboridashi

Fine, branching marks sweep across the softly domed lid of this handmade shiboridashi, like ink drawn over sand. Each dark line is the trace of mogake (藻がけ), a Japanese firing technique in which seaweed is placed against the clay, leaving distinctive patterns as the piece is fired. Their unpredictable arrangement makes every shiboridashi visually unique.

The warm, sandy-gray surface and gently speckled texture of the unglazed yakishime (焼締) stoneware provide a quiet backdrop for these expressive markings. A broad, shallow bowl, small pouring lip, and rounded lid knob give the piece a simple, balanced shape.

With a capacity of 50 ml, this compact vessel is well suited to attentive, small-volume infusions of Japanese green tea. The lid can be held slightly ajar to retain the leaves while pouring, making the preparation itself part of the experience.

Written by Sven

About Gyokko

Founded in 1961, Gyokko is a family-run shokunin pottery workshop in Tokoname, one of Japan's Six Ancient Kilns. Now in its third generation, the studio produces handmade Japanese teaware, including kyusu teapots, shiboridashi and tea cups, combining traditional craftsmanship with precision, functionality and understated beauty.

The production of a Gyokko teapot involves around 40 steps, shared among experienced craftspeople. The body, lid, spout and handle are individually shaped and carefully assembled. Particular attention is paid to the fit of the lid, the angle of the spout for a clean pour, and the position of the handle for comfortable use. The result is teaware that combines the subtle character of handmade ceramics with the reliability and refinement of skilled craftsmanship.

Below is a video of our visit to the Gyokko workshop in Tokoname, where we commissioned the teaware pieces now available at the Nannuoshan shop.

Japanese teaware categories

Japanese teaware can broadly be distinguished into three categories: kikai, commercially produced teaware; shokunin, handmade pieces made by skilled craftspeople; and sakka, works by individual ceramic artists.

Gyokko belongs to the shokunin tradition, where a master develops original designs that skilled potters reproduce entirely by hand. The emphasis is on technical mastery, functionality, and ergonomics. Rather than creating one-of-a-kind art objects, the workshop produces carefully designed pieces that excel in handling and pouring, combining remarkable consistency with the craftsmanship of handmade teaware at an accessible price.

Learn more about the three levels of Japanese pottery in this video.