Mysterious stone? Green coticule?

[Joaquinsh]

Hello everyone! I saw a stone next to a straight razor on internet, when I saw it I was almost sure it was a yellow coticule, I saw it a little dark in the photos, but I assumed that it had been used with oil and that is why it had that color. When I saw the photos of the advertisement I thought it would be a double coticule. Then, the stone arrived, and then I realized that it was not a yellow coticule, it is green, it is not a double coticule either, it is stuck to a blackboard. I haven't flattened it completely yet (I need to get some supplies for that). But if I have spent maybe 1 or 2 minutes on a 1k sandpaper, something that surprised me is that the stone, despite looking old and with a lot of use, is quite "Flat" (It's not flat, but it's not warped like I would expect it to be.). Another thing worth noting is that I tried to make slurry on the stone with another yellow coticule and.... the slurry came out yellow, not at all greenish in color, it is a hard stone, or at least harder than my two coticules.
In the photos I uploaded you can see a little of the grain that the stone has. If anyone can help me know what type of stone it is and also if you can tell me where to find information about green coticules I would appreciate it (I have tried to search and there is very little information on the internet), I don't know if it is a green coticule, but I think it is possible.

 

[David]

Can you post a few more pics of the sides and back?

 

[Wid]

Where was the stone bought?

 

[Legion]

Green coticules are not unknown. This is one of my La Verte.

 

[Joaquinsh]

Can you post a few more pics of the sides and back?

My camera is not the best, there are other photos, I can send more without problems. The back is a fairly dark color (They are two stones glued together, I'm sure of that because you can see and feel the glue (perhaps in some photos it seems not to be glued), I have very little experience in this world of stones, but I think it is not a Belgian blue, because I have one and it is very different from this, this has a constant and dark color, I can see some flashes, I don't know how to explain it, as if they were bright dots/stars. These sparkles are also in the green part (In a blue coticule that I have I can also see them, I don't know if it means something, or if it is common in any random stone). By the way, in the dark part you can see a matte area and a shiny one, the shiny one is how the stone arrived, the matte part is because I sanded it a little to see if under the dirt I could see a Belgian blue

 

[Joaquinsh]

Where was the stone bought?

I found it in an online store in my country, something similar to eBay. The seller simply sold this stone along with a Solingen straight razor, he was not a specific seller of shaving stuff. The stone is 3cm wide at the thinnest part and 3.5cm at the thickest. The thickness of the green part is about 5mm, but it is not constant along the entire length.

 

[David]

I don’t think that’s a coticule.

 

[Joaquinsh]

Green coticules are not unknown. This is one of my La Verte.

View attachment 1716864

Green coticules are not unknown. This is one of my La Verte.

View attachment 1716864

I'm very bad at searching for things on the web in English. For example I have only found one video on YouTube about a Belgian La Verte haha

 

[Joaquinsh]

I don’t think that’s a coticule.

Any idea what stone it could be? What I am sure of is that it is harder than a normal coticule and the surface is quite smooth, I also think it is a natural stone because it has veins and the shape of the stone is not square, in addition to having an irregular thickness.. I still haven't managed to sharpen a razor with my yellow coticule. But I'm going to flatten that green stone, make a slurry on it with my yellow coticule and try if I can sharpen a razor.

 

[David]

Any idea what stone it could be? What I am sure of is that it is harder than a normal coticule and the surface is quite smooth, I also think it is a natural stone because it has veins and the shape of the stone is not square, in addition to having an irregular thickness.. I still haven't managed to sharpen a razor with my yellow coticule. But I'm going to flatten that green stone, make a slurry on it with my yellow coticule and try if I can sharpen a razor.

I’m looking on my phone so I could be wrong, but take a look at the link below. From my experience it’s extremely rare for a vintage coticule to be glued to slate.

Synthetic coticule. WIP

David was nice enough to send me one of the white slate-backed vintage stones that people often assume are reform coticules. I'm going to be doing significant testing on it and posting findings here. Tonight's the very beginning. Slurry tests. Coti This stone This stone (thinned so larger...

www.badgerandblade.com

 

[kcb5150]

if it is natural maybe el globo from spain?

 

[Joaquinsh]

I’m looking on my phone so I could be wrong, but take a look at the link below. From my experience it’s extremely rare for a vintage coticule to be glued to slate.

Synthetic coticule. WIP

David was nice enough to send me one of the white slate-backed vintage stones that people often assume are reform coticules. I'm going to be doing significant testing on it and posting findings here. Tonight's the very beginning. Slurry tests. Coti This stone This stone (thinned so larger...

www.badgerandblade.com

Mmm I can't speak from first-person experience. But I have seen vintage coticles stuck to a blackboard on the internet quite commonly. Vintage I don't mean something from 1800, but maybe 40 years ago or a little more. I will go to read the publication you sent me, thanks!

 

[Shaun asleep]

I could see a Belgian blue

I would agree that it looks more like a slate when looking at the top. But perhaps it's a bbw that was oiled up? The sawed side sure resembles a bbw.
It can look like a slate if someone has used it with oil, which incindently you shouldn't do. Add some decades of use to that and you might end up with that surface?

Below is picture of an oiled up step of a staircase in Belgian Blue. This particular step is quite new, so no wear yet.

It's difficult to see on your picture nr 4, but if the top (farest away from camera) may have these typical fossils, as seen below then I would guess it is a bbw. If the lower layer is bbw then chances of the top being coticule are pretty big.

Bad news would be that is is near impossible to get the oil out of the bbw.

 

[Legion]

Bad news would be that is is near impossible to get the oil out of the bbw.

I don’t know about that. Coti and BBW clean up from oil pretty easily in my experience. Chuck them in simple green for a day or two, clean as a whistle.

It’s not like they suck it in like a sandstone.

 

[David]

I don’t know about that. Coti and BBW clean up from oil pretty easily in my experience. Chuck them in simple green for a day or two, clean as a whistle

It’s not like they suck it in like a sandstone

Agreed. I’ve never had any issues getting oil off a BBW.

 

[Legion]

Agreed. I’ve never had any issues getting oil off a BBW.

Honestly, Belgians are about the easiest hones to clean and lap as you are likely to find.

 

[SliceOfLife]

That "slate" backing is the same as on the synth barber hone coticules from a century ago.
The top is not the same but has crazing that makes me think it's probably a synth.

My suspicion is a synth/reform coti of a different type or era than what we're used to seeing... or maybe it IS one of the synth/reform cotis that got used/treated with something to cause the color change (soaked in oil maybe)... or a similarly styled/copycat barbers synth.

I mean coticule isn't impossible... but that crazing on the top is pretty much ALWAYS a sign the stone is a synth. It's most commonly seen on frictionite stones; but happens on a lot of old barber synths.

 

[Shaun asleep]

Thats interesting. I just had to have my stairs cleaned and polished by a professional because my wife treated/sweetened them with oil. She preffered the darker look, but it was a dust magnet. They had a polishing machine and needed two days to repolish the surface. Even though they are alledgedly non absorbant the dark colour remains.

You shouldn't use oil on Belgian blue stones and you shouldn't use dish washing detergent as it will damage the stone.

Straight from Ardenne Coticule:

Edit: I am no whetstone guru, just trying to pitch in with the things I have found researching and unfortunatly went through. The stairs cleanup cost me a fortune.

 

[ArtVandelay123]

if it is natural maybe el globo from spain?

Looks like it

As to the other discussion, the Coticule is a sturdy rock, it won't get damaged that easily.

I know Maurice over at Ardennes wasn't / isn't a big fan of using oil on Coticules, at all. Ergo I'm not surprised their website says this. I personally prefer water as well.
However, in many many regions the Coticule was used as an oil stone, with very good results mind you it works perfectly fine and was a widely accepted and common use of these stones for centuries.

A Coticule is also non-porous and I've lapped Coticules with over 100 years of oil use without a single issue. One quick lapping and you have a perfectly clean surface, 0 issues.

 

[Darth Scandalous]

Looks like it

As to the other discussion, the Coticule is a sturdy rock, it won't get damaged that easily.

I know Maurice over at Ardennes wasn't / isn't a big fan of using oil on Coticules, at all. Ergo I'm not surprised their website says this. I personally prefer water as well.
However, in many many regions the Coticule was used as an oil stone, with very good results mind you it works perfectly fine and was a widely accepted and common use of these stones for centuries.

A Coticule is also non-porous and I've lapped Coticules with over 100 years of oil use without a single issue. One quick lapping and you have a perfectly clean surface, 0 issues.

Yep, they were used with oil for a long time, to the point that many English language sources referred to them as "Belgian Oilstones."

I only have a few coticules but I've used oil on them--interestingly one does take on a little oil and it's the hardest, glassiest one. The somewhat softer one does not, or at least not to the extent that a quick rub down doesn't bring it back to normal.