r/NaturalWhetstones

I wanted to try some natural stones, but didn’t want to spend Dans or jnats money. So to dip my toe in the water, I snagged this batch of old oilstones labelled as naturals from a chap on Facebook marketplace.

I only know what two of them are. On the far left is a Norton hard Arkansas in really good nick - I’m really happy with this one! Centre right next to its blue box is a Salmen’s UK-made stone, which after a bit of research I think is a Yellow Lake slate. Also in good nick and a bit of a win, I think.

The other two don’t have any labels to help me. The centre left pale one could be a light Turkish stone, a Washita, or something else. The one on the far right, I’m leaning towards a Turkish stone, as I’m in Australia and they were quite common here. But it’s so filthy it could be anything under all that grime. I can’t even get it out of its box, it’s so caked up with old oil and dirt.

I’m going to give them a good soak in Simple Green for a day or two to remove the gunk so I can get a good look at them. If nothing else, it should stop them smelling like some ancient diesel engine!

Hello!

My descent into polishing and Japanese natural stones left me with one glaring issue: storage space for the growing collection of stones. With a few more stones arriving soon, I realized I would not have space for them all.

So I decided to rip off the bandaid and finally finish my very first woodworking project of any kind: my new stone shelf, which is really just a prototype that (thankfully) happens to be functional. I plan to build a more permanent option when I get back from my trip to Japan in October with improved skills and an understanding of how many stones I need to make space for lol.

The prototype shelf is made of popular on the sides with padauk shelves; both random bits of wood I picked up for super cheap to learn on. The poplar is garbage from Home Depot, but the padauk was from my local hardwood store and really beautiful. It also is very dense making it naturally fairly resistant to water; ideal for a stone shelf. I used mortice and tenon joints for the shelves, cut out some feet and sanded every edge to make it soft. There is no finish added to the wood. I used all hand tools (chisels and saws) for the project.

Let's be very honest; it's not great on the aesthetic front; there was some tear out from the shitty Home Depot poplar I used for the sides and I have an absurd amount to learn when it comes to working with wood; not against it. But it works and fits in my prep space well!

Regardless, I finished my first project, made something functional and now I have more space to grow into for the next year until I build an upgraded version down the line. For me, it felt like a win worth sharing.

I'll be back down the line with some NSDs and some more stone content. I hope you're all well!

-Teej

Background:

I found this stone hiking around Warrington, PA. It’s basically a compressed version of the red clay mud that is found all over Bucks County. I found a nice piece, squared it out a bit on a tile saw, and flattened it down with a 120 grit diamond plate from aliexpress.  It’s a fairly uniform red stone with sparkling dots of inclusions that only become visible after lapping. In most forms it’s a fairly matte and soft stone. It’s fairly resistant to chipping and cracking, and when lapped the surface turns mildly reflective.

Smell:

Fairly neutral, wet dirt.

Polishing:

Despite being a mud stone, it’s fairly hard for its relative grit. This polish lands around 2-4k in my eyes. It slurries well for its hardness, and I would call it a medium-slow cutter. I’m happy to report that the mud does grey with metal particulates, but not with immediacy. Feedback is excellent, I can feel a nice even mild grit as I make passes on the stone. It doesn’t dig in like slate, which is good. You can feel and hear off angles by tone. Similar feel to my Naniwa Chocera 3000, but with less mud and a slower cut. I find the finish contrasty, but mildly scratchy on the iron cladding. Core steel has a pleasant and unique “sparkle” to it, without being scratchy. This won’t replace a nice Suita, but I could definitely see myself experimenting with it as a hazuya stone. 

Sharpening:

I find the edge adequately refined for its relative grit. Under a microscope the scratch pattern is fairly uniform. Looking at the stone under the microscope reveals a fairly soft surface with scattered white crystalline structures… silica? Quartz? , which I believe are doing the majority of the cutting. It’s enough to shave arm hair, but it doesn’t get there quickly like a synthetic alternative. I prefer to finish harder carbon steels finer than this, but this is excellent for stainless

Notes:

This is a short one just to show you guys some kiridashi pics. I haven’t found the American Uchigumori here (yet), but I’m happy to find a native stone that actually cuts and isn’t a scratchy mess. I also cut up a bunch of scavenged slate and the patterns within the stones are quite gorgeous and some seem promising for a finishing stone. I’ll get around to that review shortly.

I made a box for one of my friend's coticule and sister stone. Because of the naturally uneven edges it was pretty difficult, and I'm using Sapele which is beautiful but hard as hell. I made it work though, and I'm gonna get a lot better as I make a few more of these.

Is there much interest in custom boxes like these?

I managed to come across this beautiful stone, which was selling at a fraction of the price of a bench size stone. This marks the beginning of a new series of posts where I'm on the lookout for bargain bin jnats.

This one is koppa size and the approx dimensions are 148mm x 85mm x 23mm. I usually prefer koppa over bench size stones when it comes to polishing, as there is less area for a blade to potentially stick to a stone and cause unwanted scratches. The size on this one is tall enough to fit on to my sink bridge, and wide enough to allow me to sharpen without causing unwanted scratches... Also saves me a lot more funds to try other stones.

The stone itself is gorgeous with all the aesthetic inlusions. First pic shows the sharpening face dry and the second pic shows it wet. We have kuro-renge on the bottom half. On the top, we have some namazu and aka-renge. The stone feedback is outstanding. With the auditory and tactile cues, I can easily tell when the stone is rejecting the blade face and creating unwanted scratches. It has a similar sharpening feel to my Mizu Uchigumori. The stone is quite soft as it self slurries easily. No need to lap up mud to create a kasumi.

Polishing wise, the stone creates a dark/high contrast finish if you work up some initial slurry - see last pic. Baking soda solution is mandatory, as the slurry is pretty reactive. It's also fantastic at producing finishing edges. Compared to other Shiro Suita stones I have (Hideriyama and Okudo). This one creates a more refined edge than the Hideryama, but not as toothy. It's not as fine as the Okudo, but it's a toothier edge and more practical for a kitchen knife. No need to introduce an additional nagura like Tsushima to add more bite.

All of these showed up in the last 24 hrs, I usually like to wait to post until I have a chance to use the stones and document the finish they leave but I couldn’t contain my excitement.

From top to bottom:

- Uchigumori bench stone
- Vnat from Zao that’s purportedly similar to Uchigumori
- Vnat from Zao that’s purportedly similar to Shiro suita
- Umegahata Aisa (3.5 hardness)
- Shohonyama fine Aoto

The uchi obviously needs to be lapped which is gonna take a while, but I’ll get a nice sized pile of uchi powder as a reward for my efforts. Photos 2 and 3 show it dry and wet respectively, look at all that renge! Massive thanks to u/pchiggs for helping me track that one down.

The Aisa currently has a toxic line on the sharpening surface but looking at the sides of the stone I think I can lap past it without losing too much height. I bought that one on a whim because the price was right and I was curious about Aisa, time will tell whether or not I find it useful.

The Aoto I’m really excited about, I have two stones from that stratum so far and they could not be more different from each other. One is in the 1-2k range and is great for edges and the other is in the 3-5k range and is a standout polisher. Both are quite narrow and this one is much wider, Ikkyu estimated the grit range to be somewhere around 5k.

A question for the hive mind: what’s your favorite method for sealing stones? I just ran out of the polyurethane spray-on lacquer I’ve been using and while I like how it performs I am curious as to what other folks here are using. I know I don’t have the patience for cashew lacquer, even though it looks beautiful.

I’ll do a more detailed review once I get a chance to test all these out, thanks for reading!

I am experiencing hard and soft spots on the stone as I sharpen
Photos in comments
Crediting u/Alphabet-soup63 for that term "tink test"

A classic piece of whetstone history. Alot of these stones were white all throughout, but not necessarily all of them. You will find examples with colors throughout and sometimes a few "wormholes" on one face or the sides. Examples of orange and pink spots are found on this spotless NOS example of a 1930s era Norton Lily White Washita. Box has a spot that was squished.
What's cool about that is I believe it was squished from packaging straps and not owner damage.

No, we have natural whetstone at home. I visited my sister today who lives next to a quarry and we went on a hike to find some pretty stones. Once we got back to her house we broke out the tile saw and cut up some pieces. I ended up with over a dozen beautiful pieces of slate, and some gorgeous red stones that are very common where I live. Some initial testing on the kiridashi proves promising. The slate feels a lot like my cambrock silkstone. The patterns in the stones are gorgeous. The red is a really fast cutter! Im still flattening these, but just stopping in to say I've got some more awesome stone writeups coming your way. Anyone else go natural whetstone hunting in their back yard?

Hardness: 5

Fineness: 5

Slurry: hard to produce

Stickyness: higher than average

Small rock of "not real" uchigumori from maruoyama mine, not an easy one to polish with but gives actually very nice fine edge with very tiny barely noticeable scratches.

Not glassy all the way and slowly starts producing slurry after a minute of work.

I figured it's about time to show off the tools that keep my knives looking and performing well. Aside from a few bench size ones I want to eventually try, I see my future with JNATs with koppa, especially with finding underrated bargain pieces or trying out examples from mines that don't get as much attention.

I've been spending several months practicing and refining my polishing technique, so hopefully these pictures also serve as a good reference for the various finishes they put on. All finishes were done on a flattened kiridashi with slurry generated from an atoma 600.

As a caveat, every natural stone is different and getting a consistent kasumi requires more knowledge and skill than the stone itself. For those who are curious about JNATs, I strongly encourage establishing your polishing fundamentals first, before easing into koppa size stones.

The stones:

Pic 1 - Bench and koppa size stones (from left to right) - Top row

• Natsuya
  • Large vintage piece, excellent particle uniformity, definitely on par with synthetics. Great for adding bite to an edge. Stropping on this with the Okudo shiro suita is a great way to touch up a blade and minimize the amount of steel being taken off.
• Aka Amakusa
  • My coarsest stone in the JNAT lineup. Gorgeous torato pattern, but can get scratchy. Mainly used to establish coarse edges that take too long on the Natsuya.
• Shiro Amakusa
  • Finer than the Amakusa or Natsuya, can clog up relatively easily. This one is considered as a Nakatoishi, however the slurry can break down to super fine particles, leaving you with a finish that Awasedo usually produce.
• Kozaki Aoto (koppa)
  • Small but mighty - medium hard aoto that cuts rather quickly, puts on a dark kasumi
• Kozaki Aoto (bench)
  • The koppa was so good that I wanted a bench size for sharpening. A lot of sandy inclusions when I got this one and I had to lap away 20g to clean up the sharpening face. This one is softer and cuts slightly slower than the koppa, but particle uniformity is more consistent. Easily self slurries and dishes surprisingly quick.
• Hard/finer Aoto
  • This one performs more like an Awasedo and is in the 4/5 hardness range. Super easy to use as a harder stone for burnishing out details. It readily accepts bevels on the sharpening surface without sticking, even if I put enough pressure until my finger tips turn white.
• Mikawa Nagura koppa
  • This one was mined in a rare strata that borders the Botan and Koma layers. As a result, it exhibits the properties of both. The finish is coarse enough to show some scratches, but also fine at the same time to reveal banding.
• Nakayama Tomae
  • Extremely hard stone and unforgiving. I'm estimating this to be 4.5/5. Too much finger pressure and you get scratches that force you back down to Nakatoishi. Dial in the finger pressure and you're awarded with a mirror like finish.
• Ohira Akapin
  • Gorgeous striped pattern when wet. Feels like a 3.5/5 hardness and produces a bright semi-mirror kasumi.

Pic 1 - Bench and koppa size stones (from left to right) - Bottom row

• Ikarashi
  • Very slow without slurry. Gives similar performance to the Aizu, but a touch coarser. Sharpening face is extremely clean with excellent particle uniformity. Can basically put on a finer version of the Natsuya kasumi.
• Aizu
  • Final Nakatoishi before jumping to Awasedo. Cuts fast without slurry and even faster with. Great as a sanity checker for flat bevels. You can realistically stop at this stone for edges.
• Hideriyama Shiro Suita
  • Finishing stone for most of my knives. As a polisher, requires precise slurry management to get a non scratchy kasumi.
• Okudo Shiro Suita
  • Not for beginners. Extremely hard stone and cuts quickly without slurry. The generated swarf is completely black. Can put on the finest yet toothy edge on a blade with proper technique. Usually reserved for my single bevels or anything that I need maximum sharpness for. Will not self slurry and tends to mirror polish. Like the fine Aoto, it readily accepts bevels without sticking. Lives up to the name of King of Suita.
• Tsushima
  • This one is an older piece that is harder and finer than the newer stones that are mined. As a polisher, puts on a bright kasumi that reveals banding. It is extremely competent as a finishing or pre-finishing stone
• Mizukihara Uchigumori
  • Great bench stone for putting on a final finish. Rated as a 3.5/5 by Maxim at JNS. Stone is pretty forgiving of bevel geometry and finger pressure, but can release larger particles that scratch up the surface ocasionally.
• Hideriyama Tomae
  • Extremely soft, coarser Awasedo that loves to generate mud. Budget friendly option for high contrast kasumi on both iron and stainlesss cladding. I used this to refinish a Kikuchiyo x Izo and the kasumi matched the OG finish.
• Aiwatani Kita
  • Similar hardness to the Ohira, but a lot more difficult to use. Rated as a 3.5/5 hardness by Maxim at JNS. Blade tends to stick with the generated slurry. Produces a darker, semi-mirror kasumi.

Pic 2 - Handheld nagura (from left to right) - Top row

Some of these serve as tomo nagura to the bench stones. I use the tsushima pretty often for the final sharpening progresion with either the Hideriyama or Okudo shiro suita. The uchigumori also gets time with polishing, as it can make some stones stick less.

• Nakayama tomae
• Okudo shiro suita
• Nakayama Akapin
• Tsushima
• Uchigumori

Pic 2 - Handheld Mikawa nagura (from left to right) - Bottom row

Super useful to have these that can change the finish a bench stone normally puts on. I also use these in several of my projects to create a bright, frosted kasumi that can start to show details. For example, the Manaka x Xinguo banding was revealed by using slurry on the Meijiro.

• Ban
• Yae-Botan
• Botan
• Tenjyo
• Meijiro
• Koma
• Ungraded

If you made it this far, I applaud you. Much appreciated for reading!

My least favorite part is cleaning them. I like this method, so far this seems to speed things up alot.

Cleaned and degreased, it is in fact a yellow color. Some say butterscotch translucent arks are oil stains, I disagree.

This was a gift to a mans brother in law in 1880, and later to his son in 1914.