[pclmulqdq]

Packing rectangular chips onto circles has waste, but that waste cannot be recycled. It has been processed through a lot of different steps that contaminate it. I'm not sure if it gets recycled, but it's going to be a lot harder to recycle than large chunks of pure silicon.

[jagged-chisel]

Ah, makes sense. I hadn’t even considered the process of etching the chips. Pretty high contaminant-to-silicon ratio for sure.

Thanks for answering!