Boron Carbide Ceramic Stone for KME (Mounted)

For KME and Hapstone knife sharpeners (KME format)
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Boron Carbide Ceramic Stone are used for sharpening knives using KME or Hapstone sharpener. The stone is available in medium grit and has an extremely high hardness rating.

Boron Carbide Ceramic Stone scarcely wears over time. Boron carbide is an extremely hard ceramic used in tank armor and bulletproof vests. Boron carbide is the third hardest known material, behind CBN and diamond.


  • Working surface: 100 x 25 x 6 mm (6" x 1" x ¼")
  • Weight: 42 g (1.5 oz)
  • Abrasive: Boron Carbide

How to use

Boron Carbide Ceramic stones should be used with one of these lubricants:

  • WD-40
  • Refined olive oil
  • Oleic aсid
  • Water

Boron Carbide Ceramic stones do not have any minor defects.

Boron Carbide Ceramic stones do not require any preparations. It is naturally lapped. This is a big advantage because the difficulty of lapping Ceramic is very high.

Q & A

  • What grit do Boron Carbide stones have?

    Grit terminology is not applicable to ceramic sharpening stones. The behavior of ceramic stone depends on its density and how good it was lapped. Our estimation is F 400 - 600 for medium grit and F 800 - 1000 for fine grit.

About Gritomatic

Gritomatic is not just an online shop. This private brand is a collection of high-quality, custom-made sharpening products. Gritomatic offers natural and synthetic stones, empty blanks and leather.

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Questions and answers

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