Years ago I was told that it had to do with the fact that the mantle forms
the pattern in Cypraea. If something (genetic or otherwise) causes it to lose
it's place so to speak, it lays the pattern down off center, over and over
again. I was also told that there is something in the water around Pony Bay
in New Caledonia where they are mostly found, that causes the shells to do
this. I've heard several reasons, but the one I've heard most often, is run
off from sulpher mines in the area. Don't know any of this for fact, just
what I've been told over the years. Have there been any studies done? I would
think so. I've been asked this question a few times and just pass on what
I've been told.
 
I think anyone who has anything to do with this great hobby is cleaver, and
also aware of the beauty that has been placed here for all of to enjoy, if we
just take the time.
 
Frank Walker
Gems From The Sea
(508) 481-7491; Fax: (508) 624-9778; out-of- state 1-800-497-3601
E-mail: [log in to unmask]   Web Site: http://surf.to/seagems