Barcelona chairs rescued from house clearance - provenance?  

Hi everyone,

My first time posting here having just discovered the extremely useful forum. I have recently come into possession (I rescued them from a friend's elderly relative's house clearance in Mexico) of two Barcelona chairs, in ivory (could just be dirty white) leather, clearly vintage (not only are they filthy but also have decades of wear and sadly the last owner seems to have had their dog on them etc) but I would love to know if they are Knoll, pre Knoll, knock-offs or otherwise... No fabric labels remain at all. The leather looks like pig skin up close as it has those tiny little pore marks/dimples if you look super closely in places. The straps are 8 on the back rest and 9 on the seat. The metal work seems to have a join under the first top end of the strap either side on the back rest, and directly mirrored beneath (exposed due to the alternating straps) The screw heads attaching the leather straps are strange, and so not sure if these have been replaced at some point. The seat cushions are filled with some sort of firm orange moulded foam with some other wadding, too, behind it and the underside is tufted fabric surrounded by the same leather as on the seat. The back rest cushions have smooth backs. The cushions all attach with what looks like a popper, not a buckle. I have only seen buckle versions, so not sure if this is incorrect or not. The back of the popper has some sort of number code.

The measurements all seem to be correct (with the cushions in place) as per Knoll's website (height, w, depth etc). They are also extremely heavy. Magnet attached with no problem.

Anyway, if anyone would be kind enough to help me out with dating them/discovering provenance, would hugely appreciate it.

Thank you!
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