eBay junker Jnats

Just when I think that I am immune from buying more natural waterstones......

Last night concluded some eBay auctions that a few of you might have been watching, of which there were a number of Japanese waterstones, both natural and synthetic. I would be the first to admit that I already have more sharpening stones than I need, but it's still fun to look, right?


Please bear in mind that I am FAR from experienced in the whole Japanese natural waterstone department, so this will be of no real value, but it is fun to guess. If anyone cares to comment and present their own opinions, this will be even more fun (at least for me!). In retrospect, I should have bought all three. Then we could do a "Guess-the-stone" roundtable. We could've sent the actual stones on a rotation, to try out in person....... THAT would've been REAL fun! Perhaps one of you bought some of these? If so, please contribute!

That said, here are the 3 that I was most interested in. The color balance of this seller's photos has changed recently, as he has started using new backgrounds with his descriptions. I have NO idea how "off" these pictures are. None of these stones had a detailed description, just size, weight, and a guess as to the fine/coarse nature, and in my experience, the seller is not an experienced user, so we get to guess.


This looks like a nice finising stone, with a fine grain structure visible on the chipped, natural edges. The greenish color with a more diffuse/mottled rosy color towards the upper edge has me thinking "Tomae". Size is about 210-72-15 mm, 1039g,  but looks like it could be sitting in a carved recess, so it may be slightly thicker. It sold for $131.50. That would be a GREAT price for a decent Tomae!

Is it a Tomae? I think of Tomae as being more tan than green, and hard.

The amount of old slurry still collected around the edges has me thinking that this would be a pretty soft stone, so it might be from a different layer. Anyone?..... Anyone?...... Bueller?......Bueller?

When I see auctions that have a number a different stones/tools, whatever, I like to imagine that there was one original owner. What did this person do? How were these tools used?  For these stones.........I am gonna guess that these were used for sharpening knives. This looks like a great stone for finishing kitchen knives, not TOO fine, and soft, to slightly ease the bevel. I like to use a slightly soft stone when finishing a large single bevel blade. This looks like a nice stone.

209-62-66 mm.  Blue/green towards white with a hint of purple specks (renge?) Some lines, with darker staining from solute migration. Some of the photos hinted at possible small white spots..... Nashiji? I am going to guess that it is some sort of Suita.

The sides are rough and dirty. I didn't see any distinct layering. This stone looks virtually new/unused, and based on the pictures, the least attractive face was used as the work surface. Was this stone just not used very much? Why?

I think that this is the opposite face. I would like to try this side. It certainly is more attractive. You can't use just any face, though (Well, you can...... but).

With natural stones that are formed through deposition/sedimentary process, the orientation of the individual particles has a significant effect on the way that the stone functions. One face can feel sticky or rubbery, yet not be effective for metal removal. It will be doing more burnishing than actual sharpening. Roll the stone 90° and it might work well, like a completely different stone. Finishing stones are typically used flat grain ie: the grain runs side-to-side. Aotos are used end grain. The grain goes up and down through the thickness of the stone.  

I bet that if THIS were the working surface, this stone would've sold for at least twice as much, and quite possibly more. As it is, it sold for $71, a steal (probably), but the hanger for me was the $55 shipping. The stone weighs 2100g. That extra 100g doubled the shipping charge, because anything over 2000g gets shipped EMS (like fedex, fast but spendy).

My mother gave me an eBay gift certificate for my birthday (Thanks Mom! How did you ever guess?!!), so feeling flush, with money to burn......

A spin of the roulette wheel. This nasty thing was identified as a synthetic stone, and I suspect that is why there was only 1 other bidder. Well..... AND it's really ugly looking. 210-65-33 mm. 727g. 

The mottled color might just be staining from sitting outside in the rain for years.

The rough edges look like spalling due to freeze/thaw cycles. It COULD'VE been a perfectly formed rectangle at some point in time.

It is significantly dished on both primary faces, top and bottom. 

There is the remnant of a manufacturers ink stamp on one edge, and you can see that it says "Trade mark". This stamp is the only thing that gives me pause (Hahahaha!.....Well, that and the whole "synthetic" thing in the description), because I have a strong suspicion that using English to identify the product means that it was intended for export. Export=mass production=crap intended for people who don't know any better (like me, haha!) I bet the eBay seller saw the stamp and thought "synthetic".

What do I like? Why do I think that this is a natural sharpening stone? 

The color is mottled on all faces, and extends into the interior of the stone. A synthetic would only show discoloration on the surface. The spalling exposed the grain structure of the stone so you can see the "inside", as it were. If you enlarge the photo, the interior looks like it HAS grain structure. A synthetic has no grain, it looks even, is amorphous. This stone shows cleavage planes and what look like small inclusions of disparate minerals. Even taking into account the spalling, I doubt that this stone was ever a perfect rectangle and a manufactured stone would be even, of course. I think it's a Jnat.

I would guess a binsui or white Amakusa, but the Amakusa's have small voids/pores and a softer particulate "feel". This looks to be a more solid, crystalline structure. I would expect it to appear almost pearlescent. Hope springs eternal, right? 

Whatever it is, it was used for sharpening knives. The dishing looks like what you get from a right handed sharpener shaping long blades. Dishing is anathema for carpentry tools like plane blades, but works very well for long edges, like kitchen knives, that don't require exact angles and would be preferred by some users. Hell, even I let the bevel get a bit convex on our kitchen knives, and I think it's clear how anal I am about flat bevels! 

I will guess that this is a natural stone, maaaaaaybe a Suita, and was used for primary bevel setting, and about #2000-3000 grit. The opening bid was $5.99, I think, and there was only one other bidder. I hoped to win it at $7, but was pleasantly surprised to learn that the other bidder had gone higher ($20), but not too high. $20 would be WAY too much to pay for an old synthetic stone, in this condition, so I am thinking that the other bidder was thinking along the same lines as me, that this is a natural sharpening stone and not some old  $5.99 carborundum sickle stone.

I guess that I'll find out soon. Any guesses?