The shell looked like a large pearlized "polished" Umbonium.
Possibly Umbonium giganteum (Lesson, 1831)
Similar to what can be found at this web site:
http://www.seashellcity.com/seashells/umboniumshells.html

A fellow shell friend and I who were watching it commented…
what is a polished Indo-Pacific shell doing in the Mediterranean?
..actually filmed in the tide pools of the Sea of Cortez / Gulf of California.

Our surmise was ... it was a gift from a goddess!
So the reality rules don’t apply!
Sad the couldn’t aford more then a half a buck for this importaint prop...
Leslie

----------------------------------------------------------------------
[log in to unmask] - a forum for informal discussions on molluscs
To leave this list, click on the following web link:
http://listserv.uga.edu/cgi-bin/wa?SUBED1=conch-l&A=1
Type your email address and name in the appropriate box and
click leave the list.
----------------------------------------------------------------------