Iga Yaki Chawan | Natural Wood-Ash Glaze | Bidoro Glass Drop | Six Ancient Kilns

Japan has six ancient kilns (Nihon Rokko-yō, 日本六古窯): Bizen, Shigaraki, Tamba, Echizen, Seto, and Iga. Each has been burning continuously for over a thousand years. Each uses local clay and local fire. And of the six, Iga has always been considered the most extreme — the most demanding, the roughest, the most willing to produce work that conventional aesthetics would call failed but that the wabi-cha (侘び茶) tradition calls masterful.

Iga-yaki (伊賀焼 — from present-day Mie Prefecture) fires in large anagama (穴窯) kilns over periods of ten to fourteen days, using split pine and hardwood. No glaze is applied. What covers the clay body at the end of the firing is entirely the product of the kiln's atmosphere: ash from the burning wood, carried by air currents, landing on the piece, melting at 1250–1300°C, and forming whatever it forms. The color that results — ranging from warm golden-amber to gray-green to deep iron-brown — depends on the clay's iron content, the ash chemistry, and the piece's position in the kiln's air flow over two weeks of uncontrolled events.

This chawan (茶碗 — matcha tea bowl) carries the full Iga surface in one piece. The warm golden-amber ash glaze covers the body in a semi-matte to matte finish, with passages of deeper orange-amber where the iron-rich clay body has burned through the ash layer. The clay's surface texture is unmistakably Iga: extremely coarse, with unfused quartz particles and feldspar inclusions visible in the body — a deliberate geological coarseness that makes Iga clay impossible to mistake for any other tradition. And on the lower body, a single bidoro (ビードロ — from the Portuguese vidro, "glass"): a small, brilliant, transparent glassy drop where ash particles accumulated, melted together completely, and ran a short distance before cooling into a permanent jewel of glass on the surface. Bidoro cannot be reproduced, cannot be aimed, and cannot be guaranteed. It is among the most prized accidents in Japanese ceramics.

In Momoyama Japan, Furuta Oribe (古田織部) designated Iga as one of the wares most suitable for wabi-cha: heavy, asymmetric, unpredictable in outcome, and honest about its own material nature. The wide, flat base and the slightly irregular cylindrical form continue in that spirit.

Very good condition. Natural ash glaze intact. Bidoro drop stable. Rough surface texture is authentic. No chips, cracks, or repairs. Unsigned. Showa period.