For sharpening experts only !!! High density natural finishing stone around 5000 grit. They are mined in Aichi prefecture in Japan. Natural stones are very rare to find nowadays and vary in dimensions and weight. They may have natural occurred flaws on the surface or on the sides. They do not need water soaking and can be used only by applying water on the surface and keep them constantly wet during sharpening. DO NOT LEAVE THE STONE SOAKED IN WATER !! Before use , take a nagura stone  to create slurry and a lapping plate to keep it flat. Clean, wipe and air dry the stone well after each use (not flat but leaning on the bench) Approximate Dimensions(depends on the stone): Weight: 1.355-1.500 gr Dimensions: L: 200-210mm/ W: 76mm/ H: 38mm