Honing slates.

[SliceOfLife]

Honing slates are an interesting thing.
You can pay $1300 for an Escher or $1 for a piece of landscaping slate.
What are the differences? How good are slates you find in your yard or random unidentified slates from a century old toolbox?

Quite a few modern hone vendors have started hawking slate hones in the past few years. They seem to spring up near where slate was already being mined for construction and other purposes. How does this come about?

Well, basically. They understand something most honers don't seem to about slate.

Slate is, almost by its definition suitably fine-grained for honing. And frequently suitably consistent. Both of these do have some variance of course and that can be noticeable in honing... but pretty much any slate you pick up isn't going to be "too coarse" for a finishing hone.

What CAN make a slate a poor or challenging stone to finish on seems to be silica content (too low and the hone is either too slow or just plain ineffective as the silica is too obstructed to effectively hone). Is this a problem for a lot of slate? Yes. Solution? Use slurry. Is it a perfect solution? No, it adds additional management of the hone and doesn't change the fact that there's a bunch of useless material interfering with honing, it just makes that material mobile enough the silica can work around it to some extent. But it is a solution for a LOT of slate that would be far less effective as a hone without it, and can even turn some slates that are quite bad hones into passable ones. What it can't do is turn a bad slate into a good one or a good slate into a great one. Slurry with slates helps correct for the stones shortcomings and can often increase speed when necessary. It is useful in situations, but isn't a magic tool to increase a slates refinement outside of quite specific circumstances. Related to and compounding this problem can be other traits of the slates makeup. Overly friable and soft stones can crumble away at the microscopic level rather than providing a consistent plane for the razor to be ground against and overly hard slates can become worn in at the surface to such an extent that their abrasion can't keep up with the wear on the edge from the act of honing... leaving the honing process treading the water of a perpetually damaged edge the hone is incapable of fixing.

Thuringians may be the go to example of an exceptional slate, both for their general suitability as a hone, and imperceptible qualities specific to them making their edges especially suitable for shaving. Still, I've had hundreds of perfectly usable slates of all sorts pass through my hands, and frankly the majority were quite useful and very reasonable options for a razor finisher if nothing else were available. Ironically, they sell for almost nothing unless mistaken for a Thuringian, La Lune, or similar iconic hone. While it's unlikely any random vintage honing slate will match a Thuringian, in my experience they tend to quite handily best the avg you'll get from the slate being sold currently as honing slate, and about one in six to one in ten seems to get up into the realm of quality that sets it apart as a quite good finisher. My suspicion is that likely slate hones were made from just about any slate that was being mined in a given region, and the ones that survived lean towards survivors bias... meaning they're the ones that were good enough to be taken care of, while the lesser examples tended to be used until something better came along and were tossed. Modern slates being dug up for paving and repurposed as "razor hones" don't have this advantage... and let's not even get into the nightmare of "barber" hones... where you'll buy twenty for every halfway useful one you get.

 

[seattleshaver]

Hones, in general, are an interesting subject. I'm no expert and I haven't gone though hundreds of hones. I do hone my own razors and have never sent one out for honing. I had dozens of razors and now have them reduced down to about 6 or 7 really nice ones.

For hones, I had what would generally be considered as "cheap" ones. I don't need to hone hundreds of razors and now that I only have a few razors, they are all done and they now all have the bevels set so, technically, I will never need to hone anything about other than "finishing".

I have a $25, full size 1000 grit King hone. It's a little slow, it's soft but it's entirely doable and how many times will the average person need to use it?

The rest of my hones are small, hand held size hones. I have a 4k, 8k and a 12k? (insert argument here ) finishing hones, pasted paddle strops (green and red) and a full size strop.

The 4k and 8k were each about $25, one finishing hone was $20 (CNAT) and the others were about $35. The paddle strops were about $10 each and the full size strop was about $20.

I get great shaves. When I first started I got one razor from Whipped Dog, so I had one razor to compare my own honing to.

As you can see, I haven't had to pay much for all of my honing supplies.

You can also pay hundreds and make a hobby out of collecting hones and enjoying the act of honing and comparing edges.

So, the choice is up to the razor owner and his/her interests but price doesn't have to be a factor if all you are interest in is ending up with a honed razor. I haven't even mentioned the film route for those that are interested in that approach.

To tie my post to the thread I also have some small slate hones (the CNAT probably is one? but I also have the slates that are sold from the UK on Ebay). It seems that once you know what you are doing, you can hone a straight with a variety of inexpensive hones.

If you have a few straights and don't use them every day it can be quite a while before you even need to go to the finishing hones for maintenance, almost making hones a moot point.

 

[SliceOfLife]

You're right. There are plenty of deals out there still. Used to be that you could get arkansas for next to nothing, then they got driven up, the 5x1" Thuri's were cheap for awhile, then they went up, small coticules sold for next to nothing for awhile, now their price is going up. There are still plenty of good deals out there though. And I think the non-Thuri vintage slates that no one cares about can be a cheap option which often gets overlooked... One I'd take before a CNAT, or a Mueller stone, or swaty, or any other "cheap" alternative I've tried.

I wouldn't worry much about what finishing stone you buy if you're using pasted stropping, as that is effectively your finisher.

When I was starting out, I did much the same as you. I had a King 1k, King 6k King 8k and $15 or so Swaty, if memory serves. I managed... but honestly there is a lot gained by going up even a small amount in investment compared to those (I absolutely LOATHED the king 1k and 6k's personally).

 

[bluesman 7]

Nice write up Ian. Enjoyable and down to earth.

 

[buca3152]

I never tried any rocks laying around as I didn't feel like going thru the lapping process. Which could be time consuming and yield nothing. But basically the stones we buy are stones. Hopefully suitable for the purpose we want to use them for.

 

[stone and strop]

I also believe that slates can vary quite a bit in hardness.
I have a purple slate from the U.K that is a finisher is every sense of the word, fantastic hone. After much debate about them, there must be some differences in them.
I recently, and have also done so in the past, tried to hone a razor on my Y/G and B/G hones and was met with reluctance by the razor itself.
It did not like those slates. The same razor DID seem to like the welsh slate and took a wonderful edge from it. They are all slates but the former being somewhat softer.
After many years of honing I have settled on a select amount of hones with varying hardness to accommodate all types of razor steels.
I know Alum of Potash has had very good success with Vermont slate as well, locally found I believe as well.
It seems to reason that to be considered slate it must be of similar composition but the amount of specific ingredients that make it up can be quite varied giving vastly different results.

 

[kcb5150]

A lot of the more interesting slates I have had have been randoms.

 

[dundak]

Nice write up. The majority of hones I use now are locally harvested slates, schists and a C13K. I’ve just love the feedback and results. It also sparks a more independent feel to the hobby.

I like what Matt at Griffith Shaving Goods is doing too. He’s sources local Rhode Island schists and pyrites for hones that work quite well.

I think people get wrapped up in the big names and literally ignore what’s under their feet. I’m a little lucky in that for a six pack I can get a rock cut and chamfered by some local sheds.

Still love a good coticule though and will buy the oddball hone to give it a run.


Sent from my iPhone using Tapatalk

 

[Gamma]

I've had a few/several garden-variety "no name" slate equal or even slightly better the resluts that Eschers are known to produce, but for me, that genre of hone is really just a breath past adequate and not really worth the fuss. I think it's great to have a nice labeled Escher of course - it's a good feeling to have "the stone' - sorta like having a nice car vs having a beat up jalopy; both get me to where I'm going but I feel better with the 'real deal' sitting in the driveway.

By definition, referring to a stone as slate infers the possibility of it having any number of qualities from a really broad spectrum of possibilities. Slate, being a development of shale, which geologists are prone to calling 'mudstone' these days, can be very short distance past 'shale' in diagenesis, or it can be much further along. With time, heat and pressure change the stone, minerals will be purged, new crystals will develop, and so on. The makeup of the prolith matters a lot, the exact process of lithification also matters a lot.

The basic rule is that the longer a stone is exposed to heat and pressure the larger the particles become. Shale is finer than Slate, which is finer than Phyllite, and so on. The grain size in a seriously indurated Slate will always be greater than what we find in a Slate that is more 'transitional' from Shale. Aside from particle size, there is silica content, particle shape, and particle size distribution. Not to mention the rest of the stone, how it holds up under 'working conditions', and how it's been stored since removed from the earth. Many slates are harder than other slates, silica content varies tremendously from vein to vein and within any particular vein. A few years ago I had a literal ton of slates here for experimenting with. Besides extreme variations from type to type, there were a seemingly equal number of variations between example within any one type.

Most stones have a certain content of silica, it's one of the more prevalent materials on the planet - the question for anyone needing to sharpen something is - will this piece of whatever in my hand serve to execute the task at hand? Many stones called slate will sharpen something, sure - but to what level of refinement? Now, subjectivity enters the arena and we find users saying MST 'faux thuringians' equal the performance of stone xyz. We also find people putting fake Escher lables on slate and I have to wonder how many people have been fooled by that guy. I remember the claims of the Dragon's Tongue being a finisher and I've never found one to be 'there'.

Over the last few years or so, I've gotten away from Eschers, they work ok, sure. They make nice shaveable edges. But the reality is that they aren't the 'killer hone' that I desire. Brain dead easy to use, yes - they are as consistent as the day is long. But they are limited and I really do want more from a finisher than they provide. I put them on top of the 'slate pile' but these days, I hardly ever reach for the one remaining example here.

 

[SliceOfLife]

What got me thinking was I've got a stack of 6 dark blue slates and 2 green slates here that I've never ID'd. Most are good, but there are a couple odd ones out that I just got recently (relatively) and never tested before. Was planning on shave testing them all to sort out the keepers again, but I decided to scope the slurry first and compare it. What I immediately noticed was that there wasn't significant difference in particle size (meaning it may vary by as much as 50%... but the particles were ALL so fine that particle size was NOT going to be the reason for a bad shaving stone). What was VERY clear was that the "keeper" stones (including both greenies) had significantly more tiny silica particles vs chaff. In fact it basically lined up exactly as the more silica, the better the hone worked. I should grab my vintage DT and add it into the mix too. Maybe a Thuri and a PDSO as well. I don't have a mueller stone here, but just by how it worked, I'd venture a guess it's quite low in silica compared to most of what I'm testing now.


As for people being fooled by fakes. I think we all know that the answer to that question is "most". Because sadly, most people who are taken in by the fakers enough to even buy from them are people who don't have the necessary frame of reference to uncover the fake in the use or even the shave. Suggestion is a powerful force, and if you read how great an Escher edge is... and you believe you HAVE an Escher... and you're a new shaver... you're going to think you've got a great edge, even if your Escher is a petrified dog turd with a photocopied label slapped on it. It'd be great if we could judge every stone and every edge in a vacuum that doesn't rely on a honers, stroppers, and shavers skill and experience all at once; but collectively that's not possible. So we can't PROVE to someone that their stone isn't as good as an Escher, anymore than we could prove to someone that the eBay special JNAT they got is a toxic piece of scrap rock the miners chucked in the refuse pile 80 years ago, anymore than we could prove to someone that Charnley Forests aren't the best razor hones ever (and won't be again until a honemeister has a big Charnley Forest collection they're looking to sell), etc etc etc.

 

[Gamma]

Slate is a very diverse material. In my wandering through many piles of slate, there were way more examples that sucked at being a finisher than there were 'keepers'. The slates that passed muster (my muster) comprise the way smaller minority. Way more - where the ratio of bad/good was something like 10 to 1. I'm talking about raw stone, not stones that were already cut to be hones. Cut stone assumes some sort of culling has gone on already.

One of the defining points for many stones is grain size and the upper limit for Slate is pretty large, where Shale's upper limit is pretty small, but you can have some finer slate but even the coarsest Shale is going to be finer most days. In a very broad sense, almost conceptually - slate always has the possibility of being a good hone but in real life most of it is more what i'd call 'tool grade'. This is at least partially why, IMO, Eschers gained such popularity. Those quarries were founded on a very large deposit of very fine stone that was uber consistent. Other types of slate hones never gained that same level of popularity because, I believe, their raw materials wasn't as fine, reliable, or consistent. Side by side honing with authentic Thuris sold as razor finishers (Fox 44, Escher, etc) show very similar results for the most part, but the same testing with piles of slate from numerous other places did not usually yield comparable results.

 

[kcb5150]

If someone just got the odd finisher level cf, it was their only example, and they had issues with hubris that's another way you get those blanket statements about them. It's an unfavorable ratio in reality and too dumb luck vs cost to be a worthwhile task to actively try for anything but a great natural knife stone and if you luck into one so be it. The finisher level ones are no joke though.

 

[kcb5150]

Ever scope slurry off a special stone?

 

[SliceOfLife]

Ever scope slurry off a special stone?

Sold all my special stones. I have got a couple Lunes I could try though.

I've had 2 or 3 Razor grade Charnleys. They weren't terrible, but they didn't hold a candle to an Arkansas... at best they were on par with lynn idwals (which are more commonly seen on eBay, sell for less typically, and are always (as far as I've seen) "finisher level"). Truth is though, I'd never recommend either for a razor finisher, unless the prices tank again. Ironically, the faster Charnleys are by FAR the better stone in my book. They're absolute treasures for knife sharpening.

 

[HippieDave]

Here is a slate hone that I'm pretty sure was cut from a patio stone. The color is grayish green and very swirly and would be very eye catching as a patio stone from the 1950s or 60s.

And here is a slate roofing tile that I cut down to size to use as a hone.

Both stones are hard but you can raise a slurry on them. I feel a bit more drag on the razor with them than I do with a Thuringian or a Belgian coticule leaving me to believe that their "grit" is not as fine but may pass as a finisher.
My straight razor shaving ability is limited so I can't tell if a stone is maybe ok, good or great but these stones are fun to play with and I like to use them as a "pre" finisher.
I only recently managed to lap flat two vintage hard Arkansas razor hones and from what I've gotten from them so far I feel that they may be a bit better than the Thuringian and coticule.

I've really enjoyed this thread and hope the photos help others see what we're talking about.

 

[SliceOfLife]

A well done Arkansas edge can be ridiculously good. Especially when you realize that a decade ago the "experts" would suggest that they were no good for razor honing. Boggles the mind.

 

[eKretz]

Yes, I remember seeing that a lot about Arks some time ago. It is nice that those of us who knew better have finally gained some ground in beating that misinformation back.

 

[SliceOfLife]

Yes, I remember seeing that a lot about Arks some time ago. It is nice that those of us who knew better have finally gained some ground in beating that misinformation back.

I'm pretty convinced it was because a lot of the PTB who ran forums and stores couldn't make a decent profit on Arkansas stones because they were already so widely available outside the straight razor hobby. We saw the same push against coticules for some time as well, but frankly Bart and a few of the other old crowd fairly effectively subverted that push just by providing alternative places to learn about them.
Why did they have to? The guys making the push happened to be selling alternatives to coticules. Some of these guys were promoting Charnley (a novaculite fairly similar and historically considered quite inferior to arkansas) as an ideal razor hone, while dismissing Arkansas. A lot of what I remember can only be explained by profit-seeking and politicking... genuine interest in helping newcomers existed, but generally got shouted down under the pretense of respect for the "meisters" in other parts of the community. And I think that had a strong enough effect that when people started talking about using a stone that was regularly used with razors a century ago, and honestly works great with them, even here away from most if not all of that environment... there was a sense that you wouldn't be believed. Before I started posting about my positive experience shaving off Arkansas, I retested it MANY times to confirm the first few shaves weren't just flukes. And honestly, I definitely undersold the quality of shaves I was getting, probably because I didn't think I'd be taken seriously if I didn't. It was that bad.

 

[kcb5150]

Yeah it got so bad with one specific individual you could post very detailed data and they would dismiss it all because they want to know what (insert name here) thinks. Is it any wonder their outreach cannibalized?

 

[eKretz]

LOL. No kidding. I got a very well used translucent Ark from my grandfather a very long time ago, so I was fortunately shown what they could do at their best right from the start. Another big issue with Arks regaining a foothold in the resurgent straight razor shaving world was the fact that a lot of guys tried to use them right after a coarse lapping, so at their best cutting speed-wise but at their worst edge comfort-wise.