Aiwadani Tamamoku・Pierre de finition naturelle・Awasedo・Shiga, Japon #104

This Aiwadani natural finishing stone comes from the Aiwadani layer in Shiga, next to Kyoto, and is stamped 相岩谷産 under the Kyoto natural-stone mark. The face is a pale straw-yellow carrying tamamoku, the ring figure that gives this layer its name. At 4,5 of 5 on our hardness scale it is a genuinely hard stone with an estimated grit around 6000: it works slowly and precisely, is sparing with slurry, and finishes bright and crisp rather than soft. Its long, narrow format suits bench work on kamisori, straight razors and carbon steel knives, where control matters more than speed. You will receive the exact stone shown.

Natural Whetstone - Aiwadani

Length: 19,2 cm
Width: 6,7 cm
Height: 2,6 cm
Weight: 862 g
Hardness: ● ● ● ● ◐ (4,5/5) hard

Sharpening Care Guide — Natural Japanese Whetstones

To preserve the character, performance, and longevity of your natural Japanese whetstone, please follow these care guidelines:

1. Keep the Stone Flat

Natural stones wear more slowly than synthetic stones, but regular flattening is still essential for controlled sharpening. Use a diamond lapping plate or a suitable flattening stone to maintain a flat, even surface. Avoid aggressive lapping unless necessary.

2. Use Water Only

Natural Japanese whetstones are designed to be used with water. Lightly wet the surface before use. Some stones benefit from a brief pre-wetting, while others should not be soaked for extended periods. Do not use oil or chemical additives.

3. Slurry Management

Depending on the stone, slurry may develop naturally during use. This is part of the sharpening process and should be managed gently. Avoid excessive pressure or artificial slurry generation unless intentionally desired.

4. Clean After Use

After sharpening, rinse the stone thoroughly with clean water to remove metal particles and residue. Use a soft brush if needed. Do not use soap, detergents, or abrasive cleaners.

5. Dry Slowly and Naturally

Allow the stone to air dry completely in a shaded, well-ventilated area. Avoid direct sunlight, heaters, or rapid temperature changes, as natural stones can crack if dried too quickly.

6. Store with Care

Store the stone in a dry, stable environment. Avoid damp locations and protect the stone from impacts or sudden temperature changes. If stored long-term, ensure the stone is fully dry before placing it in a box or wrapping.

7. Inspect Before Use

Before each use, rinse the surface and ensure it is free from dust, grit, or foreign particles. Any contamination may cause scratches on the blade and compromise sharpening results.

By following these guidelines, your natural whetstone will retain its unique sharpening characteristics and provide consistent, controlled results over time.