Dear Giancarlo,

I agree with you completely on all the points you raised. I think that most
reliable dealers do in fact either refuse outright to purchase shells with
filed lips, or at least clearly list such shells as having a filed lip.
Personally, I return any shell I receive with a filed lip or other
alteration, as a matter of policy.  I believe it is the best insurance
against receiving additional filed specimens in the future.  Collectors
should do the same with dealers.  The fact that you bought a shell through
the mail is no reason to keep the specimen if it is not satisfactory.  It
can be a bit of trouble and expense to return a shell to a dealer, and if
the shell only cost you a few dollars you might decide it is not worth the
effort - but as I said, returning every unsatisfactory shell is your best
insurance against receiving additional unsatisfactory shells. And if you
still receive filed shells from that same dealer, even after you return one,
find yourself another dealer.

As for grading such shells, I don't think there is one simple answer. First,
there are different degrees of filing. Many serious collectors will accept
an otherwise nice cone shell which has a 'lightly filed" lip, where a minor
nick was removed. But no serious collector wants a cone where the lip has
actually been reshaped by extensive filing. In my opinion, a shell with
minimal filing could still be listed as f+, but the fact of a filed lip must
be mentioned.  Some dealers will say "lip lightly filed, but otherwise gem".
That too is a reasonable description I think, as it reveals the fact of
filing, but also indicates that there are absolutely no other flaws. No
shell with any major filing should be listed as better than "fine" however.

Regards,
Paul M.