Shapton Kuromaku 320 Grit Ceramic Whetstone – Blue-Black

The Shapton Kuromaku 320 Blue-Black is a fast-cutting coarse ceramic waterstone for small chip repair, bevel resets, reprofiling, and heavy edge correction. It removes steel quickly while resisting wear, then hands off cleanly to a medium stone.

Made in Japan, KUROMAKU is Shapton’s classic color-coded solid-stone series, also known in the U.S. as Ha-No-Kuromaku, Shapton Professional, or Shapton Pro. The included ventilated case protects the stone and doubles as a stable sharpening base.

Why choose the 320 grit

Repairs small chips and rolled or neglected edges

Resets bevels and corrects edge geometry efficiently

Solid 15 mm stone offers long service life

Specifications

Brand: Shapton

Series: KUROMAKU / Ha-No-Kuromaku

Manufacturer SKU: K0709

Barcode: 4944509307092 (GTIN-13 / JAN)

Grit: 320

Color: Blue-Black

Stone type: Solid synthetic ceramic waterstone

Stone dimensions: 210 × 70 × 15 mm (8.27 × 2.76 × 0.59 in.)

Stone weight: Approximately 500 g (17.6 oz.)

Included case: Color-matched ventilated case/holder, approximately 222 × 86 × 37 mm

Water preparation: Splash-and-go; no soak required

Country of origin: Japan

How to use

Place the stone in its case/holder on a secure, level surface.

Add clean water to the sharpening face. No presoak is required.

Sharpen at a consistent angle, using light, controlled pressure and adding water as needed.

Check and flatten the stone periodically so the working surface stays true.

Care

Rinse with clean water after use, wipe away standing water, and let the stone air-dry completely at room temperature before storing it. Do not use detergent, hot water, a dishwasher, direct sun, or forced heat. Never leave the stone soaking for more than 30 minutes. If oil is used, keep that stone oil-only thereafter.

Build a Shapton progression

Follow with the Kuromaku 1000 Orange to establish the working edge, then refine further as needed. Browse the full Shapton whetstone collection.

Common questions

Does a Kuromaku stone need soaking?

No. Add water and begin sharpening. A brief wetting is optional, but long soaking can damage the stone.

Can both faces be used?

Yes. Shapton says either face can be used and recommends beginning with the unprinted side.

Does the case work as a holder?

Yes. The included case is designed to double as the sharpening base during use.