Where were herman miller eames side shells manufactured?  

Contract shells with no markings...
I've come across a contract color side shell with no markings at all. The only shells I've ever seen devoid of markings are Zenith/Venice productions. But this is the kelly green variety. My heart says authentic but my head says Modernica grass green. So that said, what do you DAers think? And have you seen this before?

Modernica
I would think the shell would be stamped Modernica. Also, the shock mounts and epoxy that they use is different.

Yeah, but...
I guess my thought was it'd be more probable for Modernica to produce chairs without markings as their quality isn't world renowned. I've seen Herman Miller chairs as early as '51 marked, both embossed and dated.
Have you ever come across one of these with no markings, woody?

Hmmm
Definitely not Kelly Green, since that would have likely been made at Cincinnati Milacron (or possibly Summit later). Do you have a photo?

Photos... Apologies for the quality. Took a few quick ones with the ole swell phone. Don't mind Bumblebee. He's asleep this time of night. On a serious note, shocks look to have been redone. [broken links]

Hmmm
It does not look like a Modernica shell to me, based on the photos. Their shells are quite thick and heavy and do not have as much visible fiber. Also, if I recall correctly, Modernica side shells have the softer turned edge similar to the older Zenith shells.
The color of your shell looks right for HM Kelly Green. If the shock mounts are original, then obviously the shell came from a stacking shell or desk. It is odd that the shell isn't stamped or labeled at all. Have you tried comparing the shell side by side to another vintage one (of any color, to be sure the shapes are identical)?
P.S. Does your shell have the wide mount positions? It looks like I can see some in the back but not the front...??

Here's the story...
The fella I bought it off said it was a "really early" one. So if that were the case, the shockmounts are all wrong. But I'm thinking he didn't know what he was on about.
There's no evidence the shocks have been repositioned. They just look like those that people are using as replacements these days. The chair does have the wide mounting points, front and back. I didn't think about that. Modernica shells wouldn't carry those would they? I haven't seen too many of them honestly.
The condition of the chair is throwing me off a bit as well. It's one of the cleanest I've ever seen. Looks as good as shells I've pulled removable pads from. I have one other kelly green shellI(the only one I've ever seen), but it's quite faded. So comparing the two colors doesn't really help at all. The shape's definitely right though.
So I guess the reasonable conclusion is Cincinatti Mil just didn't stamp it?
Or is it possible the shell was completely redone at some point(which would explain its stellar sheen) and maybe the stamp was buffed out?
Or maybe I've bought the equivalent of a unicorn here(Venice kelly green)?
I'm grasping at straws here. I realize that. Really no answers to be had. But I'm curious, like a cat...

Shell without markings does not necessarily mean early
For what it's worth, I have a shell with no markings at all that I'm certain is authentic HM but is definitely not ultra-early production. No idea who manufactured it. It came from my father's office; his office-mate brought it there sometime in the early to mid 1960s though it might not have been new then. It used to have a hopsack cloth cover, the old kind that was held on with a wire (unfortunately, totally shredded). The shell is white and the back is painted black, as HM did with upholstered shells. It has a black H base, a bit lower than dining height, with the modern style nylon glides. I could date it better if I knew when it was that the old upholstery and new glides overlapped.

We already know
The shell in question is not "early" for numerous reasons. The fact that is devoid of any markings or label remnants is puzzling. My only guess is that it could have been part of a custom contract order that requested no markings. The other possibility is that it was refinished as Lunchbox suggested.

I'm leaning towards the latter, woody...
It explains the condition of the shell, the newer shockmounts and possibly the lack of embossment. There are rewelds to the eiffel base, which are pretty well done. So it would seem someone put some work into the chair.

The shock mounts do look reat...
The shock mounts do look reattached like you say, but to me they also look pretty old, so possibly it's the original mounts which has been re-glued?
The mounts seem to have marks from a different base, not sure which one, but possibly the type of bench with 3-5 shells next to each other? Or a swivel base?
I have seen so many different variants of these chairs by now, that I'm not surprised to see a shell without the embossed markings. Maybe they simply used an older mold, while the newer molds with markings were already in use?

The mounts
Are from a stacking shell / desk.

Just to confuse everyone... Just to confuse everyone more. Here's a question. Here are three versions of the shell that I got at different places. The off-white and the upholstered Are Summit I assume. And here are the specs for each:
1. Off-White - HM embossed, BA, circled stamp that reads something like "Cent... Prime", 705302 Normal Mounts.
2. Upholstered - HM embossed, BA, HM white Label, Upholstery Label, 8121, tiny mounts.
3. Salmon - No markings just a weathered HM white Label, 022427, Normal Mounts very weathered. At least that's what Im able to make up. Viewed from the side, the legs spread apart further on the salmon. I assume the salmon/transitional one is older right? What intrigues me is the smaller/thinner shockmounts on the upholstered one plus the black iron legs look older/rustier on it too. I assume each of the legs are the ones they originally came with.
 
[broken links]

The "Cent... " stands for Century
....see earlier discussion in the thread above.

So then, Summit was the same ...
So then, Summit was the same as Century? Because the off-white has both stamps.