If I'm not mistaken, that's a swatch of fabric from Christo and Jeanne-Claude's "The Gates" given away to visitors during the first days the installation was open. If it measures roughly 2 3/4 inches square, it almost certainly is. How it came to be stuck onto that chair is anyone's guess.
I'd recommend having a DNA test done on it.
As for the chair itself, the base is likely not original (shock mounts appear to be replacements, too) nor is it a particularly unusual or desirable example. Probably commercial/institutional contract order. "Avocado" vinyl was big ca.1970.
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