Hundreds of thousands of years ago, Volcanic ashes laid thick like snow by the eruption of the volcano around Mount Horaiji-temple in the Mt. Kawai of the quartz rock. Several layers of fine tuff, the results of different characteristics resulting in the coarse grinding stone layer, there are many light-colored strata. So Nagura whetstone is called an alias and white Mikawa.
700 years ago, Sakon Nagura who lived in the village of Mikawa Nagura (Nagura Kita Shitara-gun, Aichi Prefecture), was moving in the mountain for hunting.
Stones he found on the Kawai mountain side did whet well.
At this time, the layer of the tuff which is an ore of a whetstone was discovered.
He brought the whetstone home. These stones make sharpening sword very well.
The grinding condition of a stone serves as reputation and it is supposed that the name of the stone was named the Nagura whetstone from discoverer’s Nakura’s name.
To “a Japanese and Chinese 3 years old collection of pictures” edited in the middle of the Edo era, in “whetstone for the Japanese sword, was evaluated the first-class thing by a product of Sanshu Nagura”.
From the historical flow, NAGURAwhetstone attracted attention from the samurai.
When Shingen Takeda assumed Mt. Kawai within the territory, Koshu soldier polished a sword, a spear.
Since it became the Ieyasu Tokugawa era, Tokugawa shogunate has placed the deputy official as a heavens territory and has governed the place of production.