Hi design addicts,
I would like to request your advice whether the attached ball chair is a reproduction or could be an authentic Eero Aarnio chair. I did some research online, but I’m not a professional, just a lover of timeless furniture. It has 5 inner parts, but not sure if the shell is of fiber glass. You can see the structure from a part that is damaged. Would love to hear your advice!

Congrats on your acquisition and welcome to DA Forum!
I am not an expert, but additional detail photos showing the stem joint between the base and "ball" and of the interior showing how upholstered panels are attached might help.
Your photo of the chipped edge is a bit out-of-focus, but appears to show an exposed woven fiberglass cloth layup. There are different types and techniques of structural fiberglass construction and I don't know which was used in "original" editions, but more research on this may help to determine authenticity, too.
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