Premium Japanese Natural Whetstone - Shohonyama Awasedo Shobu C for Knife Sharpening | Professional Chef & Kitchen Knife Sharpener | Perfect for Sushi Chefs, Woodworkers & Blade Enthusiasts

Length: 15.7cm

Width: 7.8cm

Height: 2.7cm

Weight: 792g

Hardness: ★★★★☆

Maintenance for natural whetstones

Do not soak in water. Water penetrates into the layer of stone, causing it to crack.

Recommended to protect the sides with cashew coating from cracking.

After use, wash with running water, wipe, wrap the stone with dry cloth and leave in a cool place. Please avoid direct sunlight.

Complimentary cashew coating service

Only available for natural whetstones you purchase from us. We offer a cashew coating for those taking extra care of the stones. It takes a week for pickup as we apply cashew 3 times on the sides and it needs to be completely dry.

Shobu - whetstone certified by the first Shogun

Shobu is known as Japan's oldest natural finishing stone. Over 800 years ago, it was presented to the emperor of the time as a premium whetstone. Then, it was certified as an official whetstone by the first appointed shogun or military leader, who established Japan's first shogunate (Kamakura Shogunate) in 1192.

Shobu was since presented as an imperial purveyor whetstone to successive emperors until the end of Showa era (1926-1989), when the mine finally ran out of whetstones.

Why is Jnat (Japanese natural whetstone) so valuable?

Japanese natural whetstones are the final destination for those seeking the best result of sharpening. At Kaz’s knife and Kitchenware, we have a variety of natural stones, most of which are Kyoto’s Shohonyama Awasedo, known as the highest-grade finishing stones. Many of the sites for natural whetstones have been closed, so natural whetstones available in today’s market are limited in number, and the prices are expected to rise due to its scarcity value.  

 

Some trivia of Jnat

The natural whetstones suited for finishing purposes are mainly siliceous slate and siliceous shale. These are further narrowed down to the ones that meet several requirements such as hardness, evenness of abrasive and absorption of water. Geographically, it is proven that Kyoto and its surrounding have the ideal stratum for natural whetstones, where layers of clay and radiolarian have slowly accumulated on the ocean floor in the equatorial regions at a rate of 1mm per a thousand years since the ancient Permian period (about 250 million years ago). Then, it traveled to the current location in Japan through crustal movement on the ocean plates.

 

Why do we sharpen with Jnat?

Popularity of Jnat has grown because of the beautiful finishing results on the blade surface. It creates the distinct contrast between the edge line and cladding steel as well as natural luster that evenly appears throughout. Exceptional sharpness is also the point why users prefer Jnat. Furthermore, its delicate abrasive performance prevents excessive grinding on the steel, which often leads to rust developed on scratches. Overall, Jnat enables more precise and even-toned sharpening.