Origin Kanji / Stamps
- Junzo Kawashiro Nagura – 純三河白名倉
- Mikawa Shiro Nagura – – 純三河白
- Not commonly found on the stones themselves.
- Inspected by Asano – 検浅野
- Should always be in red ink.
Strata Kanji /Stamps
- ムシ – Mushi
- バン – Ban
- アツ – Atsu (Thick)
- 八重ボタン – Yae-Botan (Eightfold Peony)
- ボタン – Botan (Peony)
- 天上 – Tenjou (Heavens)
- 目白 – Mejiro (White-Eye)
- コマ – Koma (Fine)
Visual Grade Kanji / Stamps – Is there a difference?
These do not indicate any difference in end performance for the strata. They are simply a visual identifier for how the stone looks and the slurry tint.
Please note the information in this paragraph is purely anecdotal. I have personally found that the Betsu Dai Jou / Betsu Jou stones are usually a bit harder and thirstier than the striped stones. It can take a bit more effort to get a good slurry going from them, and their slurry tends to feel thinner whereas the Tokkyuu/ Tokkyuu Jou have a more “cushion” feeling to their slurry. This has not impacted any performance that I have been able to measure, but it does change how they feel when used. I like the Betsu Dai / Betsu Jou better personally as I feel I have a more granular control over the slurry thickness. Price and size being equal, I would recommend Tokkyuu / Tokkyuu Jou for most newcomers as I think they are easier to get a nice slurry from and a good functional feel for the stone. I have handled 50+ Mikawa Nagura so I hope though experience reflects your own! As with all topics regarding JNATs, your personal opinion may vary.
- 刀剣用 – Sword Grade
- Bench-sized stone. It may be White or Striped.
- 別大上 – Betsu Dai Jou (Superior Selected Grade)
- White with Uniform Square Shape
- 別上 – Betsu Jou (Superior Grade)
- White with an Odd Shape
- 上特級 – Tokkyuu Jou (Superior High Grade)
- Striped with Uniform Square Shape
- 特級 – Tokkyuu (High Grade)
- Striped with Odd Shape
- 高級 – Koukyuu (High Class)