Height: 8.0 cm, Mouth Diameter: 10.3 cm, Foot Diameter: 4.6 cm
The rim is thin, the body is tapered with a distinct step, and it curves gently from the waist to the base. The small footring features fine, circular carvings around the base to add variation, and a subtle swirl pattern has been carved into the interior of the footring. The black glaze, applied leaving the footring and its sides exposed, is thin, melts smoothly, and has a lustrous finish. The glaze breaks into irregular waves, revealing the unique glazing technique characteristic of Ryōnyū. A mark known as the “middle seal”—used after the Tenmei Great Fire—is clearly stamped on the exposed clay portion beside the foot. On the underside of the lid, Chokusai has inscribed “Black Tea Bowl, Ko no Hi-go, Left (signature).”
