The flowers scattered across this bowl are not painted or printed — they are grown inside the kiln. This is hanakessho (花結晶), literally "flower crystal": among the most demanding finishes in all of ceramics, and one of the few where the maker hands the final decision to fire and chemistry.

The recipe is deliberately unstable — heavy in zinc and silica, almost free of the alumina that normally holds a glaze in place. At peak heat it turns to running glass; as the kiln cools through a narrow window held near 1,000°C, crystals seed and bloom outward into the snowflake-like flowers you see. Drift a few degrees in either direction and nothing blooms at all.

Hanakessho belongs to Kyō-yaki, the ceramic tradition of Kyoto whose roots reach back to the fifth century and whose decorative style was set in the 1600s. The crystal-flower glaze is a modern signature of that lineage — coaxed out over generations by the same Kyoto workshops known for reviving the near-lost yōhen tenmoku glaze.

Each crystal field is sealed beneath a clear, dinnerware-grade over-glaze, so the surface that meets your matcha stays smooth and durable while the bloom holds its colour beneath. Because the molten glaze runs, every piece is fired alone on a pedestal over a catch-basin, then ground free by hand — no two ever bloom alike, and many do not survive the firing.

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Made by hand, kept for years.