Japanese Natural Stones

Japanese natural stones — called Tennen Toishi, or JNats for short — are mined from ancient sedimentary rock layers around Kyoto, mainly the Narutaki district north of the city. Mines like Nakayama, Ohira, Atagoyama, Shobudani and Ozuku each produce stone with its own character — different hardness, speed and finish.

I select and test every single stone myself before it goes on the site — on razors, knives and tools. Each one gets its own description with relative hardness and best use. If a stone has any toxic inclusions or lines, I state it clearly. If nothing is mentioned, there are none.

Picking the right stone matters more than people think. If you are not sure which one fits your knife or razor, email me before buying and I will help you find the right match.

One more thing — always seal your stones, synthetic or natural, with a waterproof lacquer or by gluing them to a base. That is what keeps them lasting a lifetime.

How to use a natural stone  |  Grit, fines and hardness explained  |  Read Stone Recommendations