This stone is a Ohira Tomae Natural Japanese Sharpening Stone. Ohira is the name of the mine that the stone came from. This stone has a greenish grey hue and is very fine grit. The stone cuts fast and it doesn't glaze as much as synthetic stones. This stone weighs 2.7 pounds and measures 8 x 3 x 1 inches. Mr. Imanishi categorizes his stones high quality, medium quality and low quality. This one is a medium quality Ohira. It should give a polish finish to an edge in the 7-10,000 grit range if you were comparing to a synthetic stone.
Definate Improvement over my 6000 grit synthetic stone. and it leaves just enough bite for a tomato. Doesn’t cost a new mortgage either !!!
This is my first ever natural stone and it is the most responsive stone I have ever used. It grabs the blade road like a shark. It is very good on double bevel western style knives,especially carbon steel ones. I tried it on Misono Carbon and UX10 gyutos,and I have achieved the best edge I have ever had with these two knives. It creates an aggessive edge,but refined at the same time. Keep in mind it is a natural stone and you have to adjust your sharpening to it,find sweet spots,etc. It did not work well with yanagi,though. It has minor hard spots and also it creates a drag on the yanagi,nagura helped but I would go with a finer grit and more uniform natural stone for yanagi. I used a synthetic aoto stone before moving to this one. This combination worked well.
Really nice medium grit stone. Leaves a nice toothy edge and cuts at a decent speed for a natural. Would say it’s about 6k but as usual,if you just use the knife weight and have good mud,that number will go up. And the usual great service from Mark.