The answer is probably a 'no', but is fungi in general usable instead of just mushrooms for the theme?
fungi is metal af:
(it is debated whether the above is actually a type of fungi- according to a paper published just recently, these prehistoric trees could actually just be an entirely new kingdom/species altogether; see https://www.science.org/doi/10.1126/sciadv.aec6277)
(note that the above is also, technically, a "mushroom"- since the specific type fungus produces mushrooms)couldn't find a video on this, but: https://en.wikipedia.org/wiki/Palaeoagaracites
