Chosera Stone 4" x 1"


JIS Grit: 400


Abrasive Aluminum oxide
Available Grits 📊 Grit Chart
400 JIS M
600 JIS M
800 JIS M
1000 JIS F
2000 JIS F
3000 JIS EF
5000 JIS EF
10000 JIS UF
Bonding Magnesia bonding
Country of Origin Japan
Form Factor KME
glgc chosera
Lubricant Water
Series Chosera
Thickness of Abrasive 5-6 mm
Total Thickness 9 mm
Working Surface 100 x 25 mm (4" x 1")


Chosera sharpening stones are used for sharpening knives on small guided knife sharpeners. Chosera is a high-end series from Naniwa made of aluminum oxide with the magnesia binder. The magnesia binder gives Chosera excellent sharpening quality and performance, and high wear resistance.

Chosera series stones are universal and can be used to sharpen knives of any steel. 

Chosera should be used with water as a lubricant. Do not soak Chosera stones in water for more than a few seconds. Just splash, or use a water spray. Never store stones in water. Never dry near heat.

Attention. To reach the best result for the first sharpening session, stone lapping is recommended. Lapping is optional. During break-in period (no lapping), exposed irregularities will go away and the surface becomes smooth.

Disclaimer. For international markets, Naniwa uses names "sharpening stone" for Super Stones and "professional stone" for Chosera. Such generic names are confusing. We use more recognizable names "Super Stone" and "Chosera".