Seconding @Xenia_K here.
And it's triggered a train of thought in me, too, regarding Mycoid (or something similar) and its relationship to Meta Alloys or Barnacles.
Work with me here - but TL;DR - go down to 'Idea #2'
The previous source of Meta Alloys - known to be a defence against the damaging effects from the Unknown toxic corrosion were barnacles - and barnacles have a logo on them which must indicate an artificial source at the very least - most probably human since we love our logos.
When you go to these wreckage sites (or possibly scrapyard?) you also find similar spires to those of the barnacles - producing meta alloys, but - crucially - no barnacles.
But we do know, thanks to the messages you get at the site, that some kind of infection or other invasive nastiness was involved, presumably in the destruction of the stuff at the wreck itself. We are assuming this is the Mycoid virus because of history.
So, to recap:
1) We have a human, or at least artificial, link to the source of Meta Alloys via the logo on the barnacles
2) We know meta alloys effectively neutralise the damaging elements of unknown objects
3) We also find *only* meta-alloy producing spikes (no barnacles) at these wreck sites - along with evidence that something 'neutralised' whatever's at the wreck site.
Idea #1
Barnacles are the original (or current) source of whatever caused the destruction of the material at the wrecks - and meta alloys are potentially a product of the development of that in the barnacle - or even the seed/carrier of it.
And the reason we find meta-alloy spires at these wrecks (but no barnacles) is because that's what they were infected with, and when the wreckage arrived on-site (notice I'm not committing to 'crash-landed' because: no direct evidence), the agent responsible for the destruction started its reproduction process in the ground around it, hence new meta-alloy producing spires.
Slight issue here is that there is a general consensus that the cause of the damage to the wrecks is the Mycoid virus - and 'Mycoid' is a generic term for 'fungus-like'. Neither Barnacles nor Meta Alloys are fungus-like.
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This got me to thinking about the weird fungus farms out in the California Nebula (thanks DNA-Decay, PanPiper and others)
That's obviously suspicious as hell!!!
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Idea #2
What if actually the Meta-Alloy effect on the unknown artefacts/probes/links etc - i.e. protecting us against the corrosion - is an accidental by-product of the intended effect: To protect/inoculate Unknown objects and anything of a similar tech/origin from the infection which appears to have blighted the wrecks?
Palin described the toxic effect as a side effect of the UAs 'self-repair mechanism', and that meta alloys appear to interfere with that, thus giving us CrCrs.
We never asked: why is the UA constantly repairing itself? Well it would if it was infected with something, right?
Obviously, flowerships don't appear to harvest MAs - but they do appear to suck *something* out of those barnacles. It's not a stretch to think it must something similar to, but perhaps more fundamental than, meta alloys.
So why the logo on the barnacles? Well, again: artificial (or engineered) source - still possibly human (hidden 'allies' or at least 'friends' of Thargoids - there is a precedent), or perhaps the Thargs are also partial to a bit of labelling
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Obviously there are probably loads of logic holes and many other explanations here - this is just me taking an idea and running with it![]()
Maybe the Meta-Alloys are the "waste product" of the Mycoid?