[Panzer04]

If bones survived, some advanced remnants would also survive, I would expect.

[digging]

Maybe? Depends on what level of manufacturing and materials they achieved. Even then, not super likely. Statistically, bones don't survive that long :) It could just be a matter of time till we find a lucky break.

(Again - probably not)

[roywiggins]

Well, survived by turning into rocks: https://ucmp.berkeley.edu/paleo/fossilsarchive/permin.html

[EasyMark]

Gah, wrong comment responded to.