Not of Vegetable Origin

My previous post made me think, "What's -not- of vegetable origin, then?" The answer seems obvious, but not entirely so.

Metals are mostly not extracted from plants, although it's possible to do it. Ceramics are mostly aluminosilicate clays; glasses are only of vegetable origin insofar as they contain sodium or potassium carbonate. Other crystalline minerals normally have the vegetable components burnt or reacted out of them during the formation process — sapphire, jade, diamonds and such.

But diamonds were once coal, and coal is of vegetable origin. Marble was once limestone, which was once the exoskeletal remains of shellfish and such — and those, one presume, consumed vegetation at some point. It's hard to escape from plants — they're the main convertors of energy and raw materials into the substances everything else needs.