Okay, I'll admit my nearly complete ignorance of the practicalities of the
international shell trade. Satisfied, Emilio? But to return to the subject
of X-rays, people use them routinely to detect minute flaws in metal pipe,
to see antique art that has been painted over, and even to see bones inside
people. They could be used by dealers, collectors, and researchers to
detect some kinds of fakery after a shell has been acquired, if the need
were great enough. Filled drillholes, sponge borings, and repaired breaks
should show up on film as areas that are less dense (more exposed) than the
adjacent shell.
 
As to the practicality of using X-rays, well, the machines are expensive
and not very portable, and they do require some care to use safely. But
some university geology departments have them in their sedimentology labs,
and some medical, veterinarian, or dental clinics may allow their
facilities to be used. And then there are the industrial users of X-rays.
I've used X-rays in two research projects so far, both times to detect
sedimentary structures in cores. Some common shells turned up as well. The
radiologists at the university clinic enjoyed the break from the routine.
 
Nice posting, Paul. Very informative. Let's add Nautilus to your list of
mollusks whose lips are commonly filed smooth.
 
Andrew K. Rindsberg
Guavological Survey of Alabama