Hi All,

I am just wondering if anyone ever encountered or suspected that they were looking at fake Hyuga clamshell stones. I know there are a lot of people who try to create fake jewels and sell them cheap to tourists in some places in the world. I am wondering if there is such a thing for fake Hyuga clamshell by artificially adding color to Mexican clamshell stones or something like that. I am not going to do this, but I often look at buying stuff used at auction. I am just wondering if this exists and is something I should watch out for.

There are at least two stores in Europe that I do not fully trust regarding the clamshell stones they sell. It could be that they are just using very old prices, but...

One store has size 31 yuki stones for €450, where most others are asking €575 at least, and size 32 yuki stones for €485 (not in stock), where most other stores are at least asking €800. That same store also sells 9.2mm Jitsuyo stones for €250, where prices at other stores are around €400.

Another store even has a set of yuki size 32 stones for €400...

Note that this is just an observation about a huge price discrepancy that I can't explain, and not about the willful faking of a type of clamshell stone.

I've never heard of such a thing, Go_Japan.
But isn't it more about possible misinformation or misrepresentation?
People may be happy with shell stones and don't bother where they came from?
I think the kaya - shin kaya difference is a more likely matter of discussion (and dispute) between buyer and seller.

I don't believe they can be faked. Once you know what to look for it's actually pretty easy to tell the difference between Mexican and Native Japanese stones.

The biggest difference between Mexican and Hyuga stones isn't necessarily color, but grain. Although color plays a role in grading Hyuga stones, the grain on Hyuga stones is much, much finer than Mexican. Even snow grade Mexican stones don't compare. It's also less pronounced in Suwabute (Hyuga) stones than in most Mexican shells.

In sets larger than size 22 (and much more common in sets size 30+) there will be a few stones that will have a bend in the grain towards the center. This does not appear at all in any Mexican stones I've seen.

I could upload a few of my own photos, but I think I'll use the examples on Mr. Kuroki's site. I can only put one image up per message, so I'll just include the links for you.

Snow Grade Mexican Stones

Standard Grade Mexican Stones

Native Japanese Stones (Hyuga/Suwabute)

This is especially pervasive! I've messaged sellers about the difference when I've noticed this. In most cases it's just a simple matter of not knowing the difference and most sellers have been happy to adjust their description.

If you bought a floor board and you don't know if it's real Kaya or not, there's always the smell test. Carefully pull one of the legs from their slot (don't force if though if they don't come), and smell inside the hole or at the base of the peg. Even after decades of use the wood inside will still carry at least a hint of the sweet cinnamon smell that marks real Kaya. Make sure to put the leg in exactly the same direction it came out so as not to deform it.