Mystery Stone - ID please

[Stockman]

Picked up this one from a speculative Gumtree purchase, the seller looks like they sell second hand restaurant bits and pieces.
There were three stones in the lot and from the blurry single picture, 2 looked like junk ( and were ) and one looked interesting, thought it could have been a Turkish Stone, but I dont think/know it is not one.
Its something I have not seen or used before, but definitely a Natural.
This was how the rock arrived, it about 8"x3"x1.5"

.
After a quick clean and rub down on an Atoma 140, the stone started to show some interesting character. The front flatter surface was a nice Grey/Green appearance with orange/red mottle and gave off a grey/green slurry quite easily. The back of the stone was a very interesting red / brown and grey colour and the slurry produced was very orange.

I quickly ran my EDC folding knife onto it as it was in my pocket, and it put an amazing edge on it, probably the keenest edge I have yet to put on it. The slight cracks in the face of the stone didn't effect the sharpening, so I will probably not lap them out at this stage.

If anyone could help with the identification of this rock, would be greatly appreciated.

 

[Greasylake]

@cotedupy

 

[Legion74]

It's not a Turkish.

Looks to me like some sort of Jnat.

 

[Pie]

Th circular saw marks on the sides look like the saw marks on jnats. It’s kinda jnat sized.. it sort of reminds me of @refcast ’s dusk to dawn rainbow suita.

Either way that’s a lot of stone.

 

[cotedupy]

It's not a Turkish.

Looks to me like some sort of Jnat.

I'd probably second this; given the size, the surface crack and the unusual colouration it's not just a kinda standard slate-y whetstone I don't think.

Though note that OP is in WA, and there is another possibility that it looks quite like too. Whaddya reckon...?

Do your Mudgees have any saw marks?

 

[Stockman]

Hey cotedupey, this one came from NSW, I checked out the seller who was selling lots of bulk secondhand kitchen/restaurant products. This stone although greasy and dirty, was relatively flat, but strange scratches all over the face as shown on first pic. I was trying to figure out what the stone was used for and how the scratch pattern was made?
What’s a Mudgee, pardon my ignorance?

 

[cotedupy]

Hey cotedupey, this one came from NSW, I checked out the seller who was selling lots of bulk secondhand kitchen/restaurant products. This stone although greasy and dirty, was relatively flat, but strange scratches all over the face as shown on first pic. I was trying to figure out what the stone was used for and how the scratch pattern was made?
What’s a Mudgee, pardon my ignorance?

Ah it's not something many people would know about tbh! The Mudgee stone was something I spent quite a while trying to research a while back - the only Australian whetstone ever quarried on any significant commercial scale, and in fact from NSW.

There are almost no known examples of it, but I think it's likely that @Legion74 has actually come across a couple recently, and your stone could be too. Here are a couple of posts related to them:

https://www.kitchenknifeforums.com/threads/a-brief-history-of-sharpening-stones-in-australia.53563/
https://www.kitchenknifeforums.com/threads/the-washita-thread.53968/post-875965

 

[ethompson]

I’m voting jnat too. To speculate recklessly, I’d say it looks like it’s from an eastern mine - maybe Ozuku or aiiwatani. Impossible to say for sure though .

 

[refcast]

Yeah I'd say jnat and the orange side is a lot like kawa, I've had some jnats and the orange comes from iron oxide. The blacker color on one side too suggests kawa and jnat

 

[Legion74]

I'd probably second this; given the size, the surface crack and the unusual colouration it's not just a kinda standard slate-y whetstone I don't think.

Though note that OP is in WA, and there is another possibility that it looks quite like too. Whaddya reckon...?

Do your Mudgees have any saw marks?

No, my stones don't have those saw marks. And the face of mine are more cloudy than spotty, and they don't have the Kawa looking skin on the back, though there is a bit of orange blush on one.

Whatever they both are, I think the OP and my stones are probably different. But without knowing the variation that came from the quarry, who knows?

 

[Stockman]

Thanks cotedupy for the info, always a learning process, a bit of Aussie history is always beaut.
Hi Legion, are the Mudgee stones hard?
I had a play last night on the stone, lapped it a bit with 600 mic Sic paper and tried it out on a few kitchen knives, one with HAP40 core and the other with Blue 2. Just using water, very little slurry or swarf was created, even with high pressure, very hard stone but still felt velvety, a bit like a coti. It felt in hardness, close to my SP12,000. I did notice that after 50 or so passes each on both knives, the surface of the stone sort of glassed over, very shiny when dry, but not loaded up like a synthetic.
Lapped it with a worn diamond pad, probably 400-600 grit and created a slurry and put both knives back on, this seemed to cut/polish steal a lot better, but the edge was way too refined for how i like my kitchen knives, extremely sharp, but not toothy enough for a kitchen.
Regarding the reverse side (Kawa / iron oxide) - is this a surface that can be used to sharpen on?? This side would not take too much effort to flatten as it is reasonably flat.

 

[Legion74]

Thanks cotedupy for the info, always a learning process, a bit of Aussie history is always beaut.
Hi Legion, are the Mudgee stones hard?
I had a play last night on the stone, lapped it a bit with 600 mic Sic paper and tried it out on a few kitchen knives, one with HAP40 core and the other with Blue 2. Just using water, very little slurry or swarf was created, even with high pressure, very hard stone but still felt velvety, a bit like a coti. It felt in hardness, close to my SP12,000. I did notice that after 50 or so passes each on both knives, the surface of the stone sort of glassed over, very shiny when dry, but not loaded up like a synthetic.
Lapped it with a worn diamond pad, probably 400-600 grit and created a slurry and put both knives back on, this seemed to cut/polish steal a lot better, but the edge was way too refined for how i like my kitchen knives, extremely sharp, but not toothy enough for a kitchen.
Regarding the reverse side (Kawa / iron oxide) - is this a surface that can be used to sharpen on?? This side would not take too much effort to flatten as it is reasonably flat.

I've no idea about the Kawa side. Mine does not have that, and I've only lapped the top of mine. The stones are not super hard. Probably about average for a slate. I had no issues lapping it with an Atoma 400.

I would agree that mine is a bit refined for knives. I actually use the larger one of mine with no slurry as a razor finisher, which it does very well. Since (if these are indeed a Mudgee stone) they were sold to shearers to sharpen their shears, the first knife I tried on it was one I made out of some shears. It gave an extremely sharp edge, though as you say, not much tooth.

 

[cotedupy]

Thanks cotedupy for the info, always a learning process, a bit of Aussie history is always beaut.
Hi Legion, are the Mudgee stones hard?
I had a play last night on the stone, lapped it a bit with 600 mic Sic paper and tried it out on a few kitchen knives, one with HAP40 core and the other with Blue 2. Just using water, very little slurry or swarf was created, even with high pressure, very hard stone but still felt velvety, a bit like a coti. It felt in hardness, close to my SP12,000. I did notice that after 50 or so passes each on both knives, the surface of the stone sort of glassed over, very shiny when dry, but not loaded up like a synthetic.
Lapped it with a worn diamond pad, probably 400-600 grit and created a slurry and put both knives back on, this seemed to cut/polish steal a lot better, but the edge was way too refined for how i like my kitchen knives, extremely sharp, but not toothy enough for a kitchen.
Regarding the reverse side (Kawa / iron oxide) - is this a surface that can be used to sharpen on?? This side would not take too much effort to flatten as it is reasonably flat.

Yeah it's an interesting little bit of history the Mudgee Shearstone. I definitely wouldn't rule out yours being one, but unfortunately very little is known about what they looked like and the level of variation in them. It's certainly possible though.

The biggest thing that would count against that imo is the size. Outside of Japan stones were almost never cut wider than 2", if the Mudgee company were doing so then it'd definitely be bucking European tradition.

 

[Stockman]

Will probably remain a mystery stone, but I scrolled through thousands of Jnat pics and saw a few with similarities, also learnt a little bit about Jnats. Decided to give it a bit more lapping after work and managed to remove most of the cracks. Put a few more knives on it and starting to get an understanding for it. It is very consistent in grit, very smooth and fine. With the right amount of water and light pressure, it feels as though the edge sticks to the rock, a sensation that you are pushing the blade through plasticine. Very zen, if you love sharpening, and at a cost of 15 Australian Peso, it has been a good find.

 

[Pie]

At that price I’d be hard pressed to believe it’s of Japanese origin.

Whatever it is, good find! It sounds like a pretty good stone for a random lot.

What’s the polish look like? That can say a lot about what you’re working with.

 

[Legion74]

At that price I’d be hard pressed to believe it’s of Japanese origin.

Whatever it is, good find! It sounds like a pretty good stone for a random lot.

What’s the polish look like? That can say a lot about what you’re working with.

You would be amazed what oil and gunk covered treasures you find in junk stores and online, if you know what to look for, or are lucky. I picked up a 2.5lb Charnley Forest last week for about the price of two pints.

Not many sellers have an idea about natural sharpening stones or what they are worth.

 

[Pie]

You would be amazed what oil and gunk covered treasures you find in junk stores and online, if you know what to look for, or are lucky. I picked up a 2.5lb Charnley Forest last week for about the price of two pints.

Not many sellers have an idea about natural sharpening stones or what they are worth.

I believe it. I never ended up doing much searching in places like that, for whatever reason. I do like the antique store though, I should have a look see some time.

 

[Stockman]

This was the only pic on the Gumtree listing. What initially got my attention was the visible writing on the middle stone, looked Japanese. On further inspection of the low res pic, the larger stone with the cracks made me think that it might be a Turkish stone. I already have a turkish stone that I really like as a knife stone, but it is a touch on the smaller side. Wrong on the Turkey stone. I can see how an untrained seller could see a stone, greasy with lots of scratches and cracks and put a $15 price tag on it. As they say, "one mans junk is another mans treasure".

 

[Legion74]

This was the only pic on the Gumtree listing. What initially got my attention was the visible writing on the middle stone, looked Japanese. On further inspection of the low res pic, the larger stone with the cracks made me think that it might be a Turkish stone. I already have a turkish stone that I really like as a knife stone, but it is a touch on the smaller side. Wrong on the Turkey stone. I can see how an untrained seller could see a stone, greasy with lots of scratches and cracks and put a $15 price tag on it. As they say, "one mans junk is another mans treasure".
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What type of stone is the middle one? If it is Japanese writing that would make another bit of evidence that the big one is too. But the middle one could also be a Chinese SIC, I suppose.

 

[Stockman]

Haven't had a good look at the other 2, just pulled them out, scratched them with my nail and first impression was cheap SIC stones, very light in colour, chalky and fairly dished on the side you cant see. I will have a better look after work.

Had this one arrive today from the UK, paid 9.50 pounds + freight, about 40 Aus peso's landed.
Its a 9" x 2" x ? deep, cant budge it from the box. Nice box, will be a shame to break it. Hopefully will be able to discover its ID, once de-gunked.
Any guesses?