Naniwa P-390 Professional Stone #10000

by Naniwa


The Naniwa P-390 Professional (Chosera) #10,000 Stone is the finest polishing whetstone in the Naniwa Pro lineup. The mirror polish you can get from this whetstone is incredible, and makes you wonder why whetstones go above 10K at all.  This whetstone can help you achieve the high polished finish you see on high-end sushi knives.

The polishing effect is evident even without a lot of slurry development. Due to its density, the wear speed on this whetstone is very good, and should last years of use. 

Made in Japan


  • Origin: Osaka, Japan
  • Grit No.: #10,000 WA
  • Type: Splash & Go
  • Dimension: 210 x 70 x 20mm (8.2 x 2.7 x 0.7")
  • Weight: 717g (25.2oz)
  • Abrasivewhite aluminium oxide 
  • Cohesive agent: magnesium-bound

How to use:

Do not soak this whetstone. Simply apply water on the surface when ready to use. Rinse and wipe dry with a hand towel when done, and allow air dry at room temp. Do not leave in water. 

How to clean:

If the stone’s performance is slowing down, or seems to be diminishing, you can clean using a rust eraser, nagura stone, dressing stone, or a flattening plate. Be sure to clean the entire surface of the whetstone when using any of these methods to ensure even wear of the whetstone’s surface.


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