Japanese Sharpening Whetstone

Description

This high-quality Japanese Sharpening Whetstone is made from a blend of natural stone powder and refined abrasives, offering the tactile feedback and performance of traditional Japanese natural stones — but in a convenient, splash-and-go format.

Available in six grit levels — #500, #1000, #4000, #6000, #8000, and #12000 — it allows for everything from rough sharpening to final polishing.

One of the defining characteristics of this whetstone is its ability to create a kasumi finish: a soft, cloudy polish that accentuates the contrast between the hard steel edge and the softer outer cladding of traditional Japanese knives. This finish is valued not just for its aesthetics but also as a sign of expert sharpening.

Although no extended soaking is required, it is essential to thoroughly wet the stone before starting. Letting it absorb water for a few minutes enhances performance and helps reduce wear. During sharpening, keep the surface consistently wet to ensure optimal results, support slurry formation, and prevent uneven abrasion.

To further enhance sharpening and polishing performance, we recommend using our Nagura Sharpening Slurry blocks — available in Fine and Extra Fine types:

• Use the Fine Nagura Sharpening Slurry on stones up to #4000 grit to clean the surface and encourage effective slurry generation.

• Use the Extra Fine Nagura Sharpening Slurry with #6000 grit stones and above to refine polish, remove embedded particles, and refresh the surface.

These accessories improve sharpening consistency, extend stone life, and help achieve a more even, brilliant kasumi finish.

Technical Specs

• Grits available: #500, #1000, #4000, #6000, #8000, #12000

• Stone size (approx.): 210 × 75 × 25 mm

• Use: Splash-and-go; wet thoroughly before use and keep wet during sharpening

• Surface: Soft to medium hardness; forms natural slurry

• Finish: Produces kasumi finish on clad steel

• Recommended accessories:

  • Fine Nagura Sharpening Slurry → for stones up to #4000

  • Extra Fine Nagura Sharpening Slurry → for stones #6000 and above

What is a Kasumi Finish?

A kasumi (霞) finish — meaning “mist” in Japanese — is a traditional aesthetic effect seen on Japanese knives made from layered steel. It creates a soft, hazy contrast between the blade’s hard steel core and the softer outer cladding, achieved through careful polishing with fine whetstones. It’s both beautiful and functional, and a signature of well-honed blades.