<I strongly advise against Gary Vines' alleged solution.

How old are these nails? How significant are they likely to be? What do you
anticipate they will tell you if they can be conserved and analysed? How
much of the collection is needed for diagnosis? Are there better examples
elsewhere in the overall assemblage? Are there other sources of information
that can tell you what the nails might?

I think we sometimes get a bit precious about artefacts, analysising them to
the n'th degree regardless of how important they are.

Gary Vines