This is a stone I was recommended from Iida Tools as a pre polisher to use inbetween my Aoto or Aizu stone and my final polishers. The stone is very dense weighing in at 1.75kg or almost 4 lbs without the base, which is quite heavy for this size of stone. The stone is covered in a beautiful dark golden brown cashew laquer on 5 sides for protection. As with my other stones I have mounted it on a wooden base to make things easier and more efficient when I am sharpening. The base also stabilizes the stone on my work bench, making my sharpening a lot more consistent over time.
At first eyesight the Asagi looks a bit dull and gray in color, much like the close up picture below, but if you wet it down, a beautiful deep green and blue color with yellow tones appear. It's almost like looking down into a deep ocean on a sunny day. Fascinating!
The Oohira Asagi is a fairly hard stone, but pulls black metal particles very fast and gives up a very fine slurry after a short while, even without using a nagura. The picture below shows slurry after about 50 passes over the stone starting out with just water.
The grinding feel is really good with this stone. At the beginning and without slurry you can easily feel the grind of the stone but as soon as the slurry builds up the grinding is a pure pleasure. I have read descriptions by other Asagi owners on the web describing the feeling of a good Asagi almost buttery, and that is no exaggeration. The feeling is really smooth, almost like dragging the knife edge over oiled velvet.
When using a diamond nagura on a clean wet stone, a yellow/green slurry is produced. The slurry dries in to a light yellow/beige powder, which is a bit of a surprise considering the dark color of the stone itself.
So, what about the final result? As you can see from the pictures below, the scratch pattern on the blade road is very even, making a very nice contrast between Ji and Ha and producing a very nice mist and haze. It is obviously not a final finisher for the most demanding blades, but an edge off this stone is very wear resistant and has a very good "bite" to it making the knife very useful and efficient on most foods. A very good touch up stone i a demanding kitchen.
This sample is 20mm wide. It shows how nice this stone really is. The edge is very refined and for most of my kitchen knives this edge is actually more than good enough. This close-up also shows the excellent quality in the lamination between the two steels in my Usuba knife, also from Iida Tools.