Hi, Conch-Lers!

I know this is a common shell; it's put in every curio
basket; it turns up in crafts all of the time.  But I
can't find it in any of my books.  It has a silver mouth
(don't have a 'perc to describe), a cream ground color,
and
green and brown markings.

Can someone give me the scientific name for this thing?

Thanks,
Linda