Guido, that's a good idea although I suspect NCS would send it back with a recommendation to use a hammer and chisel.

I also suspect the glue is actually an epoxy which is not generally soluble by anything once it's cured (possible exception: 10 mole sulfuric acid

). I'm not sure a two buck Annamese or Cochin coin would be worth the conservation fee unless NCS were to share its findings.
Fred