You might want to call the store an ask.
This is for opinions of other customers not questions to the company
Not to repeat everyone's answers however it has been my experience that most businesses are not turning to their Google site to interact with consumers. To get the best answer of probably would be in your favor to call the company directly or even corporate for that matter to get the composite of what the chairs are made out of.
I'd try the Michael's website if possible
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