Aiwatani Aisa Karasu Japanese Natural Whetstone

This exceptional Japanese whetstone was selected by us and imported directly from Japan, thoroughly tested and sealed on sides and back to protect the stone for long term use. 

It measures 215 mm (8.46 inches) long × 75 mm (2.95 inches) wide × 35 mm (1.38 inches) tall, and weighs 1137 g (40.10 oz / 2.51 lbs).

Hardness: 4.2
Large and affordable Aiiwatani Aisa Karasu. This koppa is very unique in feel, likely due to a combination of a Suita layer and Aisa Layer. The stone has a dense feel with high degree of Elasticity or rubbery cushion making a Numerical measure of hardness, difficult to ascertain. These type of Karasu are more versatile than the sometimes difficult to use hardness of pure Aisa Karasu stones from Aiiwatani which are known being super hard at times. This piece is great for razor pre-finishing to finishing depending on how it's used. Most effective as a standalone hone with forced slurry and water only but can also be used for Nagura progressions. The cushioned feel quiets the nagura feedback and the stones slurry is released into the mix. For knives, it works well for edges and polishing. When polishing, the stone locks in the blade with a unique feeling of buoyancy and there is a distinct, gliding sensation which allows for accuracy in pressure management and eliminates scratching. The stone is quite grit rich and removes scratches effectively. will release a small amount of self slurry depending on blade weight and pressure used. A unique, beautiful and versatile Karasu stone at an affordable price due to the slightly irregular shape. Great value!

A photo of the stone's polishing ability on soft and hard steels of a Japanese kanna (plane) blade are shown.