Four Piece Koukyuu Nagura Set
Koukyuu - 高級
Translation: ‘High-Class’ or ‘Premium’.
Reasons why I’ve assigned the unofficial 高級‘ moniker to the larger matched sets.
1 – Each Nagura weighs 2-3x more than the pieces in the smaller sets.
2 – Every stone will, usually, be fully sealed with 3 coats of Cashew Lacquer
3 – Larger Nagura seem, to me, to be more consistent and of better quality overall.
My overall quality assessment is based on my personal experience, but is not scientific and, therefore – can be viewed as a subjective consideration.
This set is complete with all 4 of the Nagura most commonly used for honing straight razors; Botan, Tenjyou, Mejiro and Koma. Each has been fully sealed in semi-transparent Cashew Lacquer to seal the stamps, prevent the stone from shedding bits into the slurry, and to add a bit of extra strength also.
This set was in use on my bench for a long while. After culling through a large box of Nagura and testing them in a variety of combinations; I found these 4 to perform flawlessly as a matched set for my honing needs.
Botan – Betsu Jou grade: 146 g, all white, medium speed, slight grain in feedback.
Tenjyou – Tokkyuu grade: 149 g, some orange striping, faster/creamier feedback
Mejiro – Betsu Jou grade: 173 g, all white, very fine, slightly granular feel, a bit faster.
Koma – Betsu Jou grade - 131 g, all white, fast cutter, pasty feedback.