Thread: Natural Japanese waterstones update

Perhaps we had already exhausted everything we had to say on this topic, at least for now.

Oh well, here's a little contribution from me.

Hopefully not an epilogue (or monologue).

Eighteen months ago I purchased a natural aoto to provide an interim natural stone before going onto a fine natural finishing stone. The medium man-made stones (#2000-4000) leave deep angular scratches in the metal that are not desirable and difficult to remove with a fine natural finishing stone. The alternative was to work right up through the man-mades to #8000 then over to the natural finishing stone, but that was time consuming and counter intuitive.

A freshly diamond plated aoto starts at about #2000 and works up to about #4000 as you work it. From there you can go straight to an #8000+ finishing natural. The shallow abrasive pattern left by the aoto is more readily removed by the natural finishing stone.

I expect that the disappointment that some have experienced with natural waterstones comes from going straight from a medium grit man-made to a natural finishing waterstone.

The stone I purchased was a Tanba aoto that is mined (near Kyoto Kameoka) by the Tanaka family. I think I am right in saying that the aoto from this area is called Blue Mountain Aoto. I purchased mine from Ken Schwartz in the US ([email protected]). Mine is 185 x 60 x 40 mm. that cost me US$90, plus postage. They can be listed for up to $200+, but are discounted down to about $100 at times.

Ask your seller for a softer muddy stone if you are knife sharpening and for a harder stone if you are sharpening woodworking tools. I purchased mine for kitchen knives, so got a muddy one (smells like clay when wet).

My internet speed is too low tonight to post a picy, so will have to do that later. OK, just fast enough to add now...

Tanaka aota 1-m.jpg

And for those who like to see the stamps before they disappeared.....

Tanaka aota stamp.jpg

So, what do I think about this aoto?

I have grown very fond of it and increasingly I am stopping at it when touching up an edge, but it does provide the perfect interim stone if I'm going on to a fine finishing (awasedo) stone.

It is not as aggressive as say a Sigma Select II, but faster than some man-mades in the same grit range. And, it does leave a nice toothy edge for cutting food.

Neil

PS - have since come across this Tanba aoto (now sold), which has some additional information about aoto from that area. That softer one would be better for kitchen knives, but this harder one would be better for woodworkers...

PPS - and some info from So-san on the major natural waterstone quarries. The two relevant ones to Tanba aoto are Shinden and Kouzaki.

This is a very interesting subject and deserves more attention so I've decided to throw in my contribution.

I have attached a powerpoint presentation of a couple of stones which I quarried in NSW. We don't have to buy expensive Japanese stones when we can pick them up locally. Since making this powerpoint (2012) I have found a source of better stones which are not a long way short of my Japanese suita. I use the suita as a comparison (reality check) when I think I've found a really good stone. If every I find stone as good as the suita in Australia I'll start production.

I actually made this presentation for So San but he did not bother to reply so you may as well benefit.

Regards,
Gadge

Very interesting Gadge.

Must admit I have picked up some of our local chert-shale rocks, but have not had much success with any of them. They were neither aggressive nor all that fine.

Would love to see some magnified images of the abrasive pattern left by your Nakayama stone and of your two locals, as a comparison. I'm not thinking of electron microscope levels of magnification (but nice to see those of your stones), but something about 200x would do, like the following two images. The first is off the Aoto and the second after then going on to my Nakayama finishing stone.

Petty knife - 200X - side 2 - edge - Aoto.jpg

Petty knife - 200X - side 2 - edge - Aoto + Naka.jpg

Gadge, put me down for one of your Nakayama suita equivalents when you find it....

Neil

NeilS,

I've tried to get good magnified sharpening results with the stones but have been a bit disappointed with the results. I'll give it another try and post the images if they are any good. May take a week or two.

Regards,
Gadge

interesting, now I'm going to have to read the initial thread

Thanks

I re-read the old thread. Apologies for a lot of the verbal swarf in that one.

I keep playing around with local stones I've come across (also discussed in some other threads). I call them slate, but they may fall into some other geologic category (rocks would fit for sure - nothing is set in stone). Generally, grit-wise, they are finer than aoto, but certainly less than what one would call a Japanese finish stone. I have Japanese Iyoto, and I would rate them (the local stones) close together - an edge on chisels suitable for most work, but not fine enough on kanna for a finish surface, but ok for rougher work.
Everybody loves pics, so:
I tried to catch the scratch pattern (no electron micrographs) and the colour and texture of a couple of the (rocks). The stone on the left (has a greenish hue when wet, but that may be because the water is not the cleanest), is slightly finer that the other.

Steve

Originally Posted by Gadge

This is a very interesting subject and deserves more attention so I've decided to throw in my contribution.

I have attached a powerpoint presentation of a couple of stones which I quarried in NSW. We don't have to buy expensive Japanese stones when we can pick them up locally. Since making this powerpoint (2012) I have found a source of better stones which are not a long way short of my Japanese suita. I use the suita as a comparison (reality check) when I think I've found a really good stone. If every I find stone as good as the suita in Australia I'll start production.

I actually made this presentation for So San but he did not bother to reply so you may as well benefit.

Regards,
Gadge

Gadge,

Those look like great stones - would fool me (never mind the jokes) for a Japanese stone. I've looked long and hard, but nothing I've found in my neck of the world has ever come close to the fine grit of a natural finish stone.

As for Neil's original question on the cost of Japanese natural stones, I don't ever see myself spending that kind of money - not for the work I do and when there are less expensive options (i.e., lesser quality stones) available that do suit me. Doesn't mean I wouldn't love to have some, though.

Steve

Thanks Steve for sharing your stone hounding experience.

Putting aside the astronomical prices you see from time to time for the rarer and larger natural J waterstones; the cost of a more readily available fine finishing natural stone (#15000+), when compared to a synthetic of the same size and in the same grit range, is not always that much more. For example, the Shapton Pro #30,000 sell from about $450. For an overview of the average cost of some naturals, see this selection at Japanese Chefknives.

The finest finishing naturals start in the #8000-12000 range but then work up into a much finer grit.

Whether you need or wish to go into those higher grits is another matter.

Neil

Hi Sheets,

We had a gold rush here in Australia around the same time as the California gold rush (circa 1850). I quarry my stones around the old gold mining areas. You might do well to look for gold mining areas in Canada. What you are looking for is mudstone or shale. It is a very soft and muddy stone and breaks into layers like slate. If you see it cracking into layers where it is exposed and weathered then its worth a test. I take a very course diamond stone and make a little flat spot on the stone and test with an old japanese chisel or plane blade. I like to use a japanese tool as the soft jigane shows up as a black streak if the stone is cutting well. When you see the evidence of it cutting well, you can then magnify to see how finely it is cutting the hagane.

By the way, the grey stone I have in the powerpoint is also slate (I think). It doesn't cut as fast as the others but is very fine. It looks very similar to the slate you have.

Hope this helps.

Regards,
Gadge

Originally Posted by Gadge

Hi Sheets,

We had a gold rush here in Australia around the same time as the California gold rush (circa 1850). I quarry my stones around the old gold mining areas. You might do well to look for gold mining areas in Canada. What you are looking for is mudstone or shale. It is a very soft and muddy stone and breaks into layers like slate. If you see it cracking into layers where it is exposed and weathered then its worth a test. I take a very course diamond stone and make a little flat spot on the stone and test with an old japanese chisel or plane blade. I like to use a japanese tool as the soft jigane shows up as a black streak if the stone is cutting well. When you see the evidence of it cutting well, you can then magnify to see how finely it is cutting the hagane.

By the way, the grey stone I have in the powerpoint is also slate (I think). It doesn't cut as fast as the others but is very fine. It looks very similar to the slate you have.

Hope this helps.

Regards,
Gadge

Hi Gadge,

I'm pretty sure most of what I've collected locally is slate, being harder than shale. That's always the difficulty - looking at a stone and trying to decide if it will turn out to be useable. There's so much variation in what is around here (most being extremely hard and not of a consistently sized grit), my yard is littered with the rejects. I haven't been in the habit of testing stuff before I drag it home (and it has to be small enough to start with so it can be carried). In my mind, I'm constantly comparing what I see, and what I'm looking for, to examples of the finished product one would purchase (nice flat surfaces, even thickness, etc.) which is, of course, ridiculous because that's not how these things occur in nature. I can find more similar to those I posted the pics of, but I don't think I'll find anything of a finer grit.

We do have some old gold mining areas nearby, but I don't recall seeing the stones any different from that which is quarried for gravel and fill, etc. which is all basically slate or something harder. Perhaps I'll revisit and take a closer look, though (and test on-site, as you do).

Anyway, its all good fun and using natural stone instead of man-made appeals to me (and I do believe the edge produced is better - it certainly looks nicer with the misty reflection and contrast between ji and ha).

Steve

Hi Sheets,

As I said, the rock which will work for sharpening breaks into parallel layers where it is exposed to the weather. I often see rock like that exposed in road cuttings etc. If it's not in layers, don't bother. I would definitely try the stone in either of the attached images.

The consistence is somewhere between mud and rock. Keep an eye out when you drive around the country for holidays or business etc.

Regards,
Gadge

This was my miserable local effort. Possibly some sort of chert. Far too hard; medium grit but no bite.

Local waterstone.JPG

Neil

Originally Posted by Sheets

I'm pretty sure most of what I've collected locally is slate, being harder than shale. ...

You may want to take a little trip to the Burgess Shale, just be careful to not destroy any fossils you may come across.

Pam

Originally Posted by Pam

You may want to take a little trip to the Burgess Shale, just be careful to not destroy any fossils you may come across.

Pam

Hi Pam,

That would be more than a "little trip", but if I get to BC again, I'll try to fit a visit in - those are some nice looking rocks (and fossils). Closer to me, is the Bay of Fundy, which also has some famous fossil (and rock) areas. There is actually quite a history of grindstone quarrying in the area, but I don't think the rocks are fine enough for what we would be looking for. I have been meaning to go and visit the area for some time, but I never seem to make the detour whenever I'm driving by on my way to other parts of the country. I'll be sure to post about my experience if I ever do stop.

Steve