Natural Whetstone Iyo Meito / Iyo Nagura from Karakawa, Ehime, Japan

A traditional Japanese natural whetstone, Iyo Meito (伊豫銘砥), from the historic province of Iyo (modern-day Ehime Prefecture, Shikoku, Japan). This natural abrasive can be used either as a standalone intermediate sharpening stone or as an Iyo Nagura for raising slurry on harder Japanese natural finishing stones.

The original Japanese description uses the traditional spelling 伊豫銘砥, where 豫 is the old form of the modern character 予. For this reason, both 伊豫銘砥 and the modern spelling 伊予銘砥 may be encountered.

History of Iyo Meito

The Japanese seller describes 古代伊豫銘砥 — Ancient Iyo Meito as a traditional Japanese whetstone with a history of approximately 1,500 years, reportedly quarried since the Kofun period. Iyo is regarded as one of Japan's ancient whetstone-producing regions.

The name can be interpreted as:

伊豫 — Iyo — the historic Iyo Province.
銘砥 — Meito — renowned or celebrated whetstone.

Thus, 伊豫銘砥 — Iyo Meito can be translated as “Renowned Whetstone of Iyo.”

Sharpening Characteristics

According to the Japanese seller, natural Iyo Meito stones from this group have a broad approximate working range of #800–4000. As with all natural stones, this grit rating should be considered approximate: actual performance depends on the individual stone, water, pressure, and slurry development.

The stone readily releases abrasive particles and produces a useful slurry. This makes it suitable for several applications:

• as a standalone intermediate sharpening stone;
• as an Iyo Nagura on hard Awasedo stones to quickly raise slurry and accelerate the initial sharpening stage;
• for cleaning the working surface of another whetstone and removing metal loading;
• for preparing the surface before progressing to a finer Tomo Nagura or finishing directly on the clean base stone.

Iyo is particularly interesting as a Nagura for hard Kyoto JNATs, where it can quickly create an initial abrasive slurry on very hard Awasedo stones that otherwise release abrasive material only slowly.

For an extremely fine final finish, Iyo Nagura can be followed by a finer Nagura or Tomo Nagura, with the final polishing stage performed directly on the clean finishing stone.

Features of This Stone

This particular stone has a natural muted pinkish-beige to light brown coloration with a relatively uniform fine abrasive structure.

The face retains the traditional blue stamp:

伊豫銘砥 — Iyo Meito

The stone is shaped as a convenient rectangular Koppa (木端). Its relatively large working surface means that it can be used not only as a Nagura but also as a small standalone sharpening stone.

Specifications

• Name: Iyo Meito / Iyo Nagura
• Kanji: 伊豫銘砥
• Type: Japanese natural whetstone / Nagura
• Origin: Iyo, Ehime, Shikoku, Japan
• Dimensions: approx. 100 × 75 × 14 mm
• Weight: 230 g
• Approximate grit range: #800–4000
• Density: approximately 2.5 g/cm³ for this material group, according to the seller
• Shape: Koppa
• Stamp: 伊豫銘砥
• Recommended for: knives, woodworking tools, intermediate sharpening, and raising slurry on hard JNAT finishing stones

Use as a Nagura

Simply wet the surface of the main whetstone and rub the Iyo Nagura over it several times. The resulting slurry increases cutting action and helps initiate sharpening on very hard Japanese natural stones.

On fine #8000–12000+ Awasedo, Iyo is best regarded as an initial Nagura rather than the final finishing stage. It can then be followed by a finer Nagura or Tomo Nagura, gradually refining the slurry before completing the final honing directly on the base stone.

Iyo Meito is an interesting traditional Japanese natural abrasive combining historical character with practical sharpening performance. It is particularly useful for owners of hard Kyoto Awasedo stones who want to raise an effective working slurry quickly.