DWhatley;178375 said:
What is the chance that the pearls are the by-product of dinner? While looking for jewelry recently, I saw a
posting that claimed a pearl was found inside an octopus. I didn't put much faith in the post but it occured to me that consumption of a clam might include consuming an undigestable pearl and that pearl material might not be so foreign to the body of a relative that it might be harbored internally and pushed out of the way in some fashion. I did not know that nauts created them at one time and your post reminded me of my thoughts while reading the octopus pearl post.
I suppose this would be called a thread-hijacking. But perhaps it's the most appropriate way to introduce a peripheral subject such as biomineral concretions in cephalopods!
Any living thing produces anomalous concretions, bezoars (kidney stones) etc, whether to call it a pearl is subject to debate. There are those that insist that 'pearls' only be nacreous, for example.
I know Dave LeBlanc, he is describing a biomineral concretion resulting from a cyst, and his octopus 'pearl' is taken seriously by the pearl community, for its undeniable provenance and one-of-a-kind.
In addition, there is one lab-certified
Argonauta pearl, and a total of about half a dozen Nautilus pearls. But these certifications have been given on anecdotal provenance, not scientific proof of ID, as no Westerner in a position to judge has been on hand to witness the actual finding (unlike Dave LeClare and his octopus!).
Only Nautilus among
Cephalopoda has an exterior shell, which is primarily nacreous. Problem is, for several centuries all reports of loose Nautilus pearls (vs. blisters)—held as powerful talismans by Indo-Pacific natives for their rarity and the mysterious nature of the animal itself—have been of non-nacreous, or porcelaneous, concretions. This has created great debate in the pearl community, since the Nautilus shell is predominantly 'pearly' (nacreous) and one would expect the pearls to reflect this. Thus my conversations with Peter Ward and other top mollusk and shell microstructure scientists here and in Europe, regarding the incredible complexity of the Nautilus biomineral factory, which led to all the others. It is an ongoing journey involving Paleozoic evolution of the mollusk shell possible dormant genome sequences.
By the way, my avatar is a backlit microscopic view of a small (3.1 carat) purported Nautilus pearl, with a characteristic vortical swirl at the pole. Quite fascinating!