Eames walnut stool split  

I don't think it is strictly ...
I don't think it is strictly possible to say without photos showing the split and how it is situated in the grain and in the stool. I can imagine situations where it would be of ongoing concern and others where it would be a stable crack of minimal concern.
Post photos.

Cracked.
One of my Eames stools has had the same crack problem for over 20 years. It is still as solid as the other two. I blame Ray Eames.
As always,
Aunt Mark

And crack just works well for...
And crack just works well for the temperament of that stool.

Please note that it's not rea...
Please note that it's not really a straight line if that makes a difference. Let me know. Thanks.

Do you have a photo of the si...
Do you have a photo of the side? I am curious how far down the cracked piece of wood goes.
Edit: if I had to guess, I'm looking at face grain so that board will not extend very deelyp, which might be more concerning.

I don't. But I think the spli...
I don't. But I think the split stops at the bottom of the lip where it starts to curve inward. Much appreciated

Crack
Whether or not the crack will worsen depends on the age of the stool and the conditions that it is kept in.

What form of
stool is this ? Is there an Eames stool with a solid hardwood disc top ? I don't think we're looking at a turned stool here. What kind of legs does it have ?
The crack may be a development which started with a hidden check (crack) in the wood. It would have advanced to this state after the piece was exposed to substantial changes in atmospheric humidity or temperature. Or the wood could contain stresses which are relieved by the opening of this check. If the disc can be separated from its legs, the disc could be cut along the line of the crack and glued.
Wood movement is a fact of life. Look at Mark's walnut stool: different pieces of wood have grown or shrunk since it was on the lathe. Only the adhesive is limiting the extent of the movement and keeping the stool in one piece. This is a separate issue from the visible check . . .

SDR
The top appears to be comprised of (at least) three pieces of wood glued together.

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oops.

oh my.
I ask for a discount on that lovely piece.
Best,
Aunt Mark

If there were more photos, I...
If there were more photos, I could envision a few cases where I wouldn't be too worried, structurally speaking. BUT by the same token I can envision many other cases where I would be quite worried about it getting worse.
So, on balance I'd be wary of that crack, and I wouldn't think it is likely to be an immediate structural problem. But it could open the doors to all sorts of further warping and splitting because it goes clear through that piece of wood.
And aesthetically speaking you can't "fix" that crack. To be precise, you could perhaps fill it today, and it would be "perfect", and in a few month when the humidity is different it will have opened wider or crushed the filler out.

I couldn't figure out how to ...
I couldn't figure out how to upload pix without my computer and I'm on my phone. I saw more pix with the split, it's across the surface and goes down to the vertical part of the lip and maybe half an inch inward as the stool curves in. And I can't see it in person.
I"m trying to get back to the seller soon, so let me know what you think. Thanks!

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