Verdigris On IHC?

MY CAMERA IS MISSING. (There's always something, isn't there.) However, up for question is a 1906 IHC--the gem of my collection, really. She was my finder's fee when I graded a bunch of old wheathead books for my former boss (and then purchased the books, including eight IHCs and a whole bunch of 1911-1929 wheaties plus steelheads and more common wheats, for ten bucks because she wanted rid of them--score!), and--problem in the subject bar notwithstanding--I think she might actually grade UNC, definitely AU (no wear on the cheek and under a strong light and a loupe I can see hair detail I didn't know to look for until the "damaged" lot I posted the other night).

So, here's the question: I was told that if the verdigris has "hardened," there's no point in removing it. This beauty sat in one of those old, cheaply-glued, cheaply-dyed cardboard folders for 40+ years and was in this shape when I got her, and I didn't notice anything "slimy" or "growing" about the verdigris when I first got her--I actually thought it was a kind of toning from sitting in that old blue folder.


Should I be worried? Should I pick up some Verdicare, or am I setting myself up to damage an otherwise beautiful coin?