I acquired an Aluminum Group mid-back lounge recently. It has the old four-star base that uses the hex screws. However, I noticed that the Herman Miller logo underneath the bottom antler support seems to be worn down. Is this a sign that the aluminum was refinished at some point? It certainly doesn't look refinished but who knows what this thing has been through in its 40+ years of existence. I'm just curious as to how that part of the aluminum logo could be worn down like that. 
It doesn't look like anything
beyond the normal production finishing of any polished cast metal part to me. If you don't see any further evidence of disassembly/reassembly, don't worry about it. The finisher just laid on the abrasive wheel a bit too long, possibly to remove a nasty burr or mold flash. Consider it the human touch of hand-craftsmanship. There's plenty of the mark left intact to confirm authenticity.
I agree
It could be factory - going hard on the polishing wheel, but I suspect it is a refinish - and for that, I would not be concerned at all.
Refinishing wood by removal of its original finish is often necessary but many argue it devalues. Paints and varnish have changed over the years etc.
But when it comes to metal, there is only one way - buffing and it has to be done until pits are removed.
If anything, it has added value to your piece - one of the few things I consider (and I know others think this way) you can actually add value rather than leaving it to further pit etc.
Seriously, it has enhanced the piece if redone and it was done darn well too I may add.
Thanks
Thanks for the insight. Both posts have eased my mine, whether it was refinished or not. Although, something about the overall condition of the metal just screams 40 years of wear. Additionally, the seller of this chair had two from an estate sale. The Herman Miller logo on the other aluminum group was not worn down at all. But that chair had already been sold to someone else.
I hate to bring up an old thr...
I hate to bring up an old thread, but in case anybody searches for this issue in the future, I would like to add that my early Aluminum Group chairs (four-star contract base, hex screw attachment), both show quite a bit of wear where the Herman Miller logo and patent info is stamped to the bottom antler. These chairs were never refinished and came as such from the factory.
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