When you attribute the "CA" monogram nacre, please
attribute this one, too. It should be easy, as it
even has the casino name engraved into the pearl.

http://www.netmar.com/~creator/benedict/mopov1.html

I can show you at least 20 pearls all having a
"CA" monogram that we have no idea as to where
they're from.

If I had to take a wild guess, I would say it was engraved by the house of Caro (Paris) in the late-19th Century...for use in a European casino (more than likely France).

JB