Suehiro dark kasumi/finish after Naniwa super stones on Moritaka blue2 ?

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Soli

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I have two new Suehiro stones, and a question about the finish/ colour left after polishing the back bevel with them.

A little bit of background: previous stones are Naniwa super (400, 3k, 1/5k combo, 12k—finisher for my straight razor) and Chosera (1k—love this stone). I lap them with a Lee valley stone (200 grit?) as the 400 grit SS dishes quite quickly.

I just got the debado 200 (which is huge!) and rika 5k in the mail from Adam over at the Cook's Edge. I'm Canadian and heard good things about these stones from the reviews on the forum. Adam seems like a good dude.

Spending some time with them today on my thinning and re-finishing project, which is an old Moritaka B2 240 gyuto I used to use in a pro kitchen as a workhorse. Both of these stones left a surprising dark finish on this knife. My supers leave a mirror polish at 3k or above, and yet the 5k Suehiro actually darkens the mirror from the 3k SS. Is this the elusive kasumi?

Grit progression was 150 sandpaper, 200 debado, 400 ss, 1k chosera, 3k ss, then 5k rika. After years of neglect I thought to spend a few hours with the new stones. Taken a fair bit of metal from this old Moritaka. Anyone else find the Suehiro stones leave behind this dark finish when sharpening? Pics will come when I try to force a patina (kurouchi is long gone).
 
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adam92

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My suehiro cerax 1k also leave quite ( dark ) kasumi.
 

mrmoves92

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My Rika 5k leaves a kasumi finish, and the 220/200 grit stones that I have used have all left a lot of contrast. Does the effect that you are describing happen when you are polishing with your Chosera 1k? I get a really nice looking kasumi finish (for the grit) with my NP1k.
 

Pie

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This might be more of a process thing than a stone thing. No doubt different stones will leave different finishes, but most stones can give varying finishes when used under different conditions.

#1 - super stones are exceptional at making high polishes. They will almost always give you a cleaner, brighter finish than other stones of similar grit.

Haze/kasumi/cloudiness, whatever we want to call it, is created by loose grit rolling around while abrading - accomplished by using a thicker, heavier mud while polishing, and using short strokes. Alternatively, clean water and long strokes will give a much shinier finish with a visible scratch pattern at middle grits. Your chosera is *extremely* good at showing this. If you’re up for it, I suggest trying the 2 techniques on opposite sides of the knife and see how it reacts.

I suspect the rika is quite soft, and produces some nice mud, giving you the haze that the super stone doesn’t.

IME moritaka’s blue #2 polishes up very easily, and his iron cladding is nice to work with. Short, flatter bevels makes polishing easier than some others. You picked a good polish mule!

14734C8D-DFD6-43F4-A252-1CCD2940ED6C.jpeg

Moritaka cladding happily gets hazy while leaving the core steel high polish. Roughly 3-5k stone, as well, but with a good amount of mud.
 
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