Nautilus pearl

[SteveM]

Perhaps the next question could be whether pearl sacks and detached pearls of this kind are possible at all. Is there any known to date?

Lagoon Pearl's octopus 'pearl' seems to hold the singular honor of offering a verified result of calcareous concretion in cephalopods.

But this thread has recently been growing 'tentacles' that promise additional revealing contributions. The malacological branch devoted to Cephalopods is called Teuthology (a new one to me). So just to be sure this thread is reaching its proper audience:

TEUTHOLOGISTS WELCOME !!

(Lay terminology preferred.)

 

[Valeria101]

The malacological branch devoted to Cephalopods is called Teuthology (a new one to me).

Same here - some things are so old they are new to most!

 

[GemGeek]

Jeremy, that's a fabulous find. Thanks for sharing it here.

 

[Lagoon Island Pearls]

I have the same question as Valeria,
How can it be that a tissue different from the mantle or bone secret a calcium concretion?

While most cephalopods don't have shells, they do have beaks.

Beaks are often erroneously compared to fingernails. Fingernails are keratin, which is a complex protein. Beaks are formed by chitin, which is a long-chained polymer of acetylglucosamine, a carbohydrate derivitive. Although different, they are similar in structure.

The affinity between chiton and calcium carbonate or aragonite is well known, particularily in the exoskeletons of crustaceans and of course.... pearls. Most studies however, show a distinct absence of calcium compounds in the beaks of cephalopods. The likely reason being, acids from digestion prohibit formation.

To me, this gives rise to the plausibility of pearl formation in cephalopods, particularily by nucleation. I am not aware of anyone experimenting with this, but it certainly holds some intrigue. Pearls from bivalves are much more common because of the susceptibility of their environment, whereas cephalopods have evolved away from this factor. As opposed to most mollusks, rather than becoming sedentary to the benthic zone at metamorphosis, cephalopods remain pelagic.

Interestingly enough, I'll refer everyone to a paper published by the Royal Society on the trophic ecology of cephalopods, including giant and colossal squids.

http://rspb.royalsocietypublishing.org/content/272/1572/1601.full

I found one section to be most interesting with respect to nautiluses.

"Beak samples were not acidified because, to our knowledge, chitinous beaks of cephalopods do not contain significant amounts of carbonates, except those of nautiluses (Clarke 1986)."

Yet another wrench thrown into the gears of our understanding of this amazing creature's physiology.

 

[GemGeek]

That is very interesting!

 

[waimeamomi]

OK, I have to jump in this is too interesting and makes me think of my semester of Invertebrate zoo in college. The cuttlefish is also a cephalopod and fits into the evolutionary "train" between the nautilus and the squid. It has a significant internal shell made of calcium carbonate.

 

[GemGeek]

Not my favorite eating (Dad made me eat it sashimi-style), but you can carve the bone and make castings with it. And what parakeet doesn't love that bone? Cephalopod trivia.

 

[DrTKStern]

Jeremy's "Blister"

Jeremy's "Blister"

Lagoon Pearl's octopus 'pearl' seems to hold the singular honor of offering a verified result of calcareous concretion in cephalopods.

But this thread has recently been growing 'tentacles' that promise additional revealing contributions. The malacological branch devoted to Cephalopods is called Teuthology (a new one to me). So just to be sure this thread is reaching its proper audience:

TEUTHOLOGISTS WELCOME !!

(Lay terminology preferred.)

Nautilus Blister Hunters and Interested pearl lovers,

First, isn't this fun! And what a GREAT CONTRIBUTION by Lagoon Pearl.

Second, with dinner at stake, in this particular matter I'm holding out for a pearl on a stalk, with said pearl exhibiting a cosmic swirl, which will end all doubts.

Third, I feel the hot breath of a pearl hunting dragon and have told my men to GET MOVING!!!!!!!!!!!!!!

Happy New Year to all.

Tom

 

[SteveM]

I'm holding out for a pearl on a stalk, with said pearl exhibiting a cosmic swirl, which will end all doubts.

That's clear, albeit pending GIA's report on the ability to confirm a match for the detached blister pearl and shell!

Re swirl, I'm adding the montage below as my prior photo shoot included the back side of the 7mm button (not the blister), that manages to show a perfect continuation of the swirl pattern into the opposite hemisphere.

That said, while these swirls may eventually prove to be a characteristic typical of top Nautilus pearls (nacreous or not), it is probably a stretch to think of it as a requirement, just as Queen Conchs are not necessarily deep pink and symmetrical with flame.

(Maybe we should open wagers on how many pages this thread is going to run before a definitive conclusion is reached?)

 

[DrTKStern]

GIA and Lagoon Pearl

GIA and Lagoon Pearl

That's clear, albeit pending GIA's report on the ability to confirm a match for the detached blister pearl and shell!

To all,

Yes, with all of the equipment at their command, I absolutely acknowledge the ability of GIA to determine if the cat nautilus pearl came from the same Nautilus stalk. They can do micro xray, plus optically magnify 100 times or more, and match fine lines. The opinion of a match by GIA would entitle Steve to a delicious banquet in San Francisco, with other local pearl lovers invited.

Very exciting. My stalwart men report we have found an octopus pearl; and I will send photos as soon as they arrive. They say it is lovely to look at and has magical properties of protecting its owner, much like a Nautilus pearl. I hope to be able to get this pearl to GIA soon, and wonder if Lagoon Pearl might be willing to submit his octopus pearl to GIA to enlarge human knowledge, if no cost to him.

Best to all,
Tom

 

[GemGeek]

Great news. Personally, I hope this thread never ends. The world of natural pearls keeps expanding, so why shouldn't this thread?

 

[Lagoon Island Pearls]

Very exciting. My stalwart men report we have found an octopus pearl; and I will send photos as soon as they arrive. They say it is lovely to look at and has magical properties of protecting its owner, much like a Nautilus pearl.

Awesome! I'm eager to hear the story behind the find.

I hope to be able to get this pearl to GIA soon, and wonder if Lagoon Pearl might be willing to submit his octopus pearl to GIA to enlarge human knowledge, if no cost to him.

Best to all,
Tom

Of course! It's my hope something profound could be gleaned from it's inspection. If I may, I'd also like to submit a couple of my mussel pearls for inspection, including ones that could be cut or ground.

 

[Caitlin]

The ever-deepening spiral into special pearls keeps getting better and better. It's spinning out as a universe; tentacles included. I am so happy I get to read about it here. Thank you all!

 

[Lagoon Island Pearls]

Hats off to Jeremy Norris!
Now...acting the contrarian...is that a blister pearl or a ridge of nacre initiated by a worm? Is there a distinction?

This question has been rolling around in my mind as well.

While pearls can form in many parts an animal, my studies indicate the greatest incidence are proximal. This is usually due to an acid-base imbalance in that part of the tissue or the blood itself, where crystalization can occur, for whatever reason.

The attatched photo of a mantle section, supports this theory.

I have observed single specimens with 1000s of micro pearls throughout the entire mantle, indicating chronic imbalances in blood chemistry.

In a minority of cases, pearls are formed by injury, irritants or parasites.

Regarding this particular nautilus, the formation has the appearance of being distal, but is likely proximal, because of parasitazation from the outside inward.

Scale worms (Arctonae vittata) are commonly present in gastropods, namely Gumboot Chitons (Cryptochiton stelleri), Keyhole Limpets (Diodora aspera) and some seastars. Having a shell, this relationship is likely in the nautilus as well. Perhaps someone with hands on experience with live nautilus specimens could elaborate further.

Ed Ricketts best describes this relationship: "The length of the worm, considering the size of the host is remarkable, and the worm has to curl around the mantle so completely that it's ends almost touch. Even more remarkable, perhaps, is the response this worm gives when it's host is attacked by by the predatory seastar Pisaster ochraceus. The scale worm, as if understanding that it's host's demise would also be it's own, seeks out the seastar's tube feet, bites them and usually causes the seastar to loosen it's grip and withdraw."

While the relationship between worms and their hosts is often described as commensal (a form of symbiosis in which one organism derives a benefit while the other is unaffected), it would appear to be mutual in this case.

I have never observed a live nautilus, so I'm merely being speculative, but it's seems apparent from these photos that an immature scale worm is the underlying factor in the formation of the blister. Likewise, occurring in the latter stages of the natilus' life.

 

[SteveM]

I have never observed a live nautilus?

Thanks again for such great detail. Sure you're not a scientist?

Back to Professor Peter Ward, I've been catching up on his seminal works from the 1980s, 'In Search of Nautilus' and 'Natural History of the Nautilus', the first of which details all significant observations of Nautilus from Aristotle forward.

'In Search of Nautilus' is an amazing summary of mankind's interaction with this fascinating mollusk and I highly recommend it. Barnes and Noble appears to have a lock on a number of used copies at the ridiculously low price of $1.99. But you'll have to look harder for 'Natural History' as it's a collector's item and seems like $200+ is the going price.

Hoping to have that talk with the Professor soon?

Back to practical matters, below are photos received from Bali of a found Nautilus pearl together with its mollusk, and a closeup of the bottom of the pearl with that eyecatching swirl. I'm not anatomically adept is the pearl coming out of the animal's EYE?

These photos are from the same source as the blister posted by JNorris, claimed to be the only 2 blister or pearl examples this source has found out of 25,000 Nautiluses caught and processed by his company in the past five years. This pearl is clearly porcelanous (non-nacreous) in composition to counter the blister's nacreous surface.

Back to square one?

 

[GemGeek]

That looks strange. Perhaps they just placed the pearl on the Nautilus for the photo?

 

[Lagoon Island Pearls]

Sure you're not a scientist?

Quite sure. I am a technician and producer/director though, so my skillsets allow me to research things as to cause and effect. Couple that with my passion for pearls and living in an environment which allows me to participate in these studies, makes for a fascinating hobby.

That looks strange. Perhaps they just placed the pearl on the Nautilus for the photo?

My thoughts exactly. Certainly not "in situ", and not likely the same animal.

A magnificent find nonetheless, though.

 

[SteveM]

That looks strange. Perhaps they just placed the pearl on the Nautilus for the photo?

The pearl certainly screams tridacna, despite the swirl. But as credibility of the source for the nacreous blister is related, vigilance is essential.

The pearl was sold to a London jeweler and natural pearl reseller.

 

[GemGeek]

It doesn't seem fair that there isn't some kind of difference discernable through spectography between tridacna and nautilus. <sigh>

 

[SteveM]

It doesn't seem fair that there isn't some kind of difference discernable through spectography between tridacna and nautilus. <sigh>

You can understand my excitement much earlier in the thread upon discovering Prof. Vincent Barbin's research paper applying Cathodoluminescent Scanning Electron Microscopy to Nautilus shells (Barbin's team was integral to NASA's Mars landing missions for CL SEM robotic soil analysis). He was able to distinguish between outer shell and septum, also he documented distinct and consistent manganese curves for the Nautilus subspecies Pompilius and Macromphalus that he concluded to be genetic and not environmental in origin. Most important (to eventually matching pearls and shells), the CL profile was consistent in the nacreous and non-nacreous layers of the outer shell.

I did manage to get a response from Prof. Barbin saying that pearl application had not been tried. No pearl lab to my knowledge has or uses this technology.