The 1/10,000mm Miracle

In 1593, Maeda Toshiie (前田利家) began gold and silver leaf production in Kanazawa, where the climate created ideal humidity for handling ultra‑thin metal. When the Edo shogunate later banned leaf-making outside Edo and Kyoto, local artisans continued in secret, refining techniques. Now, Kanawaza supplies over 98% of Japan’s gold leaf.

The alloy is first prepared by the sumi-shokunin (澄職人). Pure gold mixed with small amounts of silver and copper is gradually rolled thinner until it becomes uwazumi (上澄), a delicate base sheet.

At the same time, haku‑uchi (箔打) artisans make the specialized ganpi‑fiber (雁皮) papers required for beating. The paper is dampened and struck at high speed and this is repeated many times over the course of more than four months before any gold is added. Once ready, the gold is pressed between these papers and struck until it expands to just 1/10,000 mm in thickness, so fragile that even a breath can tear it.

Kanazawa gold leaf still adorns cultural treasures and remains essential to Japanese crafts and art, continuing to find new ways to bring light into our everyday world.