Hey Folks,
OK!  I guess we have our answer!  Don't! Sheesh!

The reason I asked questions was that the whole thing sounded destructive. 
Some of the instructions I found online even described coating the fossil 
with india ink, which, once again, sounds very destructive, not to mention 
the idea of Bon Ami in an air brush.  Which was why I was asking.

Under no circumstances would we put anything on the fossil that would hurt 
it.  I have experience handling and preparing fossils, and of course we 
don't want the fossil to fall apart.  But I do have to take it out to look 
at it. :D   BTW, we put it on a velvet pad instead of the cotton, which was 
how it came from the museum.

But I still wish someone would be willing to answer a few questions -- Like 
why ammonium chloride or burning magnesium strips?

best, Julia Morgan Scott

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