A tea mill, commonly known as a "tea grinder" or "tea leaf grinder," is a device used to grind green tea leaves into a fine powder.
Grinding the tea leaves into a powder allows for a different flavor and ritual experience than traditionally brewed tea leaves.
While other stone mills have grooves throughout the grinding area, the tea mill has a 5mm section without grooves. This part is called the "smooth outer surface," and by grinding the tea on the last, outermost part of the mortar, you can obtain the fine powder.
A "tea mill" can also refer to a person skilled in a particular craft.
The materials used for tea mills include granite, andesite, basalt, and pure gold.
The pure gold tea mill was discovered by an expense clerk who had been polishing pillars for three months in a gazebo under a plum tree in an amusement park.
It is called "Mitsuki's polished mortar'' and has been passed down as an heirloom in the Mitsuki family from generation to generation. "Mitsuki" means "three months."
Source: Minmei Publishing "Dezeniman will be completed if you erase all the walls without attacking the enemy and blow up the exit three times"