Thread: Coarse natural stones?

Please forgive me if this is a repeated question. In a couple weeks when school's over (at least THIS semester) I'll be able to dig a little deeper into old posts.

I haven't started learning to hone yet, mainly because I don't have a good progression. I've ended up with a few barbers hones, and a natural Japanese stone from Old School. And now that you mention it, there's a Thuringian on its way.

Aside from the barbers hones I've already got, I'm thinking it would be really cool to stick with natural stones. So my question is this: Are there any natural stones that take the places of the DMT's and/or Norton 4k?

That's a good question. The closest natural stone I'm familiar with to a Norton 4000 is a Belgian Blue. I've found that when the Belgian Blue stone is used with a piece of Belgian Blue slurry stone (I think I have one slurry stone left that I'd sell out of an 8"x3" that I had cut up for that purpose), the cutting ability of the Belgian Blue with blue slurry approaches but does not equal the speed of the Norton 4000. There are many many natural stones from the Belgian Blue all the way on up that are polishing stones. But...good question on a 4000 or lower grit natural stone. I have not had any experience with any.

The Ardennes mine in Belgium that quarries the Belgian Blue and the Yellow Coticule stones sells a Belgian Blue stone that is manually bonded to a manufactured carborumdum coarse grit stone making it a two sided combo stone. The call is a "Cotcarb" stone. The problem is the carborundum side is rated at 600 grit which is IMO too coarse for razors.

Chris L

There's a thread called Natural bevel, with some discussion about natural hones and their suitability for bevel setting. No one in that thread has any natural stone for bevel setting.

I think if you wanted a coarse natural hone, then looking into Japanese hones might be worthwile.

Even if you go all natural, it might be worthwhile to have a DMT 8C for flattening and maintaining your stones.

These days I lap my stones pretty much before each use (or after each use ) which
a) makes it easy and painless to keep them flat
b) insures consistent honing behavior.

With a DMT plate, I just have to hold them under running water, rub a couple of times, rinse off and continue.
I have never liked working with sandpaper on a plate. Way too messy, and too much work to do regularly.

And some naturals are very hard. meaning you won't have to lap them often, but when you do, sandpaper is very slow (did I mention messy? )
And a norton flattening stone wouldn't work because it is softer than most naturals so it would wear quickly.

Originally Posted by chancecatalyst

Aside from the barbers hones I've already got, I'm thinking it would be really cool to stick with natural stones. So my question is this: Are there any natural stones that take the places of the DMT's and/or Norton 4k?

Well, as for lower grits to set the bevel Arkansas stones can go down to almost 320 grit I believe. Washita is the coarsest grade, the Soft Arkansas is the next step up, then the Hard Arkansas, then the Black Hard Arkansas (or Surgical Black), then the Translucent Arkansas is the highest grit coming in at anywhere from 4k to 8k (reports vary, widely).

But the vendor and the quality of his stones play a large part in how fine the grits really are (I think a general rule of thumb is that the vintage ones are finer). And some people don't like the Arkansas stones because they are supposed to be used with oil, but I have used them with water, though not extensively, and they seem to be fine.

But whichever you decide to get, do yourself a favor and get the DMT 325, makes lapping any and all stones a breeze.

Originally Posted by Chrisl

That's a good question. The closest natural stone I'm familiar with to a Norton 4000 is a Belgian Blue. I've found that when the Belgian Blue stone is used with a piece of Belgian Blue slurry stone (I think I have one slurry stone left that I'd sell out of an 8"x3" that I had cut up for that purpose), the cutting ability of the Belgian Blue with blue slurry approaches but does not equal the speed of the Norton 4000.
Chris L

In my mind, the Belgian blue is more of a polisher than a cutter. I've tried using it with a slurry and pressure to remove small irregularities in edges, and I always end up dropping down to a hone like the Norton 4K or DMT 1200.

The blue seems to remove scratches from coarser hones fairly efficiently, but once you have achieved a certain level of polish, it doesn't do much. Possibly I'm just really impatient.

I think Bruno once used Belgian hones to restore a badly damaged edge, and it took something like 10 hours of heavy grinding.

Originally Posted by Russel Baldridge

Well, as for lower grits to set the bevel Arkansas stones can go down to almost 320 grit I believe. Washita is the coarsest grade, the Soft Arkansas is the next step up, then the Hard Arkansas, then the Black Hard Arkansas (or Surgical Black), then the Translucent Arkansas is the highest grit coming in at anywhere from 4k to 8k (reports vary, widely).

I've heard that the Arkansas stones are so hard and slow-cutting that they behave like much finer hones. I've heard of guys shaving off of an Arkansas hone that's roughly 1K in grit. I don't have any direct experience, though, so I might be wrong.

My thought is that a 320 grit Arkansas might act more like a 1K or 4K hone. I'd be interested to learn more about this myself.

Josh

Originally Posted by Chrisl

That's a good question. The closest natural stone I'm familiar with to a Norton 4000 is a Belgian Blue. I've found that when the Belgian Blue stone is used with a piece of Belgian Blue slurry stone (I think I have one slurry stone left that I'd sell out of an 8"x3" that I had cut up for that purpose), the cutting ability of the Belgian Blue with blue slurry approaches but does not equal the speed of the Norton 4000. There are many many natural stones from the Belgian Blue all the way on up that are polishing stones. But...good question on a 4000 or lower grit natural stone. I have not had any experience with any.

I agree with JoshEarl on this one, my belgian blue does not even come close to the cutting speed of the Norton 4K; the blue is a polishing stone that cuts much slower and leaves a much more polished edge than the Norton. I typed a longer response to this question before but my computer got timed out and it was erased. Basically the main point was that Dave Martell, master Japanese Knife sharpener, said that with very few exceptions that natural stones below 1K are junk and synthetic stones above 1K are junk. While I don't agree with the second statement I think that synthetic stones below 1K are much better than the naturals that claim to be in this grit range.

Josh, I have shaved off of lower grit (and high grit) arkansas hones to see how they perform. Personally, I still prefer the coticule edge to this, though they were passable. The issue with low grit arkansas hones for bevel setting is that they generally have a high level of inclusions and are VERY slow cutters. Though the inclusions generally won't cause any damage to the blade, they will make it cut even slower. I think, again, this would take as much time as using a coticule, even though you have dropped to this lower grit. IMHO, totally not worth it, get a 1200 grit water stone.

Originally Posted by JoshEarl

I think Bruno once used Belgian hones to restore a badly damaged edge, and it took something like 10 hours of heavy grinding.

Something like that yes. 10 hours of heavy grinding on a yellow coticule with slurry. It was 14 or 15 hours in total, but 5 hours were spent on a very coarse stone that didn't cut worth jack.

Coticules are great, but just because you CAN do something like that doesn't make is a good idea.
I did it because I had nothing else. It works great, and it taught me a lot.
but I don't think I'll do it again.

Originally Posted by Bruno

Something like that yes. 10 hours of heavy grinding on a yellow coticule with slurry. It was 14 or 15 hours in total, but 5 hours were spent on a very coarse stone that didn't cut worth jack.

Coticules are great, but just because you CAN do something like that doesn't make is a good idea.
I did it because I had nothing else. It works great, and it taught me a lot.
but I don't think I'll do it again.

Plus it's a lousy way to wear out a beautiful natural hone like a coticule...

Josh