About Ishiusu

The ishiusu is a traditional Japanese millstone used to grind tea leaves into the finest powder for matcha. The art of tea cultivation and preparation has a centuries-long history in Japan, and the Ishiusu represents one of the finest facets of this tea tradition.

These mills are not made by machine, but are intricately shaped by hand by experienced master craftsmen. The choice of material is of crucial importance: the millstone is made of a special volcanic rock that has the ideal hardness and capillarity to grind the tea leaves evenly and gently. This volcanic stone is often sourced from regions such as Nara Prefecture, which is famous for its high-quality millstones.

The process of making an Ishiusu requires precision and dedication. First, two circular stone slabs are formed, which must fit together exactly. The surfaces of these slabs have fine grooves that run across the stones in a spiral pattern. These grooves are crucial for the grinding process: they enable the leaves to be crushed gently and the gentle pressure to be distributed evenly over the ground material.

A master grinder understands the complex interaction between the various parameters - from the hardness of the stone to the humidity of the matcha and the external climatic conditions that influence friction. Every adjustment to the shape and depth of the grooves can change the character of the final matcha.

During the grinding process itself, the leaves are placed in the central opening of the upper stone. With a circular hand movement, the upper stone is rotated over the lower one, which continuously grinds the leaves between the two plates. Patience is of the utmost importance here: it takes about an hour to produce fifty grams of matcha with one ishiusu. However, this artisanal slowness makes it possible to preserve the natural aromas and nutrients of the tea leaf in the best possible way.

The use of an Ishiusu adds another meditative dimension to the tea ceremony. The slow, rhythmic grinding process creates a connection between the tea master and the material, between the present and ancient traditions. In addition, the Ishiusu is often seen as a symbol of the patience and appreciation inherent in the enjoyment of tea.

The Ishiusu is more than just a tool; it is a symbol of the purity and perfection that characterizes Japanese tea culture. In a world where haste and efficiency often take center stage, the Ishiusu is a reminder that true art is created through time and leisure. It remains not just a means of making matcha, but an expression of the timeless wisdom of traditional craftsmanship.