Nautilus pearl
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SteveM
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Money is definitely the issue. Two major gem labs have told me they've studied the possibility and have determined it to be unfeasible. One cites lack of sufficient organic matter, especially in non-nacreous pearls?which comes off as superfluous justification.DNA matching? Can they do that with a pearl and shell? Maybe we can take up a collection...
In coming months I will be pursuing ID issues with institutional researchers currently involved in the study and artificial replication of nacre. The Nautilus's unique combination of nacre structures (bivalvian and gastropodian in adjacent shell locations) has perennially made it among the most desirable shells for scientific study. Oddly, its nacre characteristics remain the least understood of all mollusks.
SteveM
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Spirit of Nautilus willing, below are images upon receipt of our two most recent discoveries.
Top row is the 3.5ct/8mm semi-round silver/blue pearl that reportedly was barely adhering to the apertural region of the shell of a Nautilus fished within the past 15 days. The pearl was removed easily with the fingers, leaving scant telltale mark on the pearl. My guess is that it's predominantly porcelanous, with a brushing of nacre that took place following the pearl's tenuous attachment to that particular region of the shell.
Bottom row is the fully flamed (but only stubbornly chatoyant) 8.05ct/10.5mm semi-round pearl from an old collection, vortex/spiral structure on BOTH top and bottom.
Scientific Research:
We have been led back to Spain and the preeminent work on shells and nacre (with emphasis on the origin and nature of spiral patterns) of Dr. Antonio Checa of the University of Granada. Dr. Checa's work is among the most prominently cited in the continuing efforts to manufacture nacre for industrial and medical use.
Dr. Checa saw images of our vortexed pearls, and although they are not nacreous, expressed an intense desire to study them. At the same time, Nautilus has held his fascination for years due to its unique combination of bivalvian (terraced) and gastropodian (columnar) nacre deposition. A study of the potential nature of Nautilus pearls would involve all the same steps as the study of Nautilus shells, and our sources in Indonesia could prove valuable for the obtention of the required fresh specimens.
We will visit Dr. Checa in his University of Granada offices in June. At that time, we will also meet with biologist colleagues of his specialized in Proteomics, who have indicated that DNA—while not endemic to non-cellular extrapallial secretions such as nacre and conchiolin (like human hair)—may be found in the form of 'contamination' by extruded DNA from adjacent mantle tissue cells.
Dr. Checa, also a Paleontologist, knows the work of Peter Ward well and relied upon Ward's seminal works on Nautilus biology when researching Ammonoid septal formation in the 1990s. Small world! (And yes, he will also receive bottles of our producer's wine grown near the Cambrian dig depicting Trilobyte Mureriense on the label!)
Now we just need to decide which pearls are to be sacrificed.
Top row is the 3.5ct/8mm semi-round silver/blue pearl that reportedly was barely adhering to the apertural region of the shell of a Nautilus fished within the past 15 days. The pearl was removed easily with the fingers, leaving scant telltale mark on the pearl. My guess is that it's predominantly porcelanous, with a brushing of nacre that took place following the pearl's tenuous attachment to that particular region of the shell.
Bottom row is the fully flamed (but only stubbornly chatoyant) 8.05ct/10.5mm semi-round pearl from an old collection, vortex/spiral structure on BOTH top and bottom.
Scientific Research:
We have been led back to Spain and the preeminent work on shells and nacre (with emphasis on the origin and nature of spiral patterns) of Dr. Antonio Checa of the University of Granada. Dr. Checa's work is among the most prominently cited in the continuing efforts to manufacture nacre for industrial and medical use.
Dr. Checa saw images of our vortexed pearls, and although they are not nacreous, expressed an intense desire to study them. At the same time, Nautilus has held his fascination for years due to its unique combination of bivalvian (terraced) and gastropodian (columnar) nacre deposition. A study of the potential nature of Nautilus pearls would involve all the same steps as the study of Nautilus shells, and our sources in Indonesia could prove valuable for the obtention of the required fresh specimens.
We will visit Dr. Checa in his University of Granada offices in June. At that time, we will also meet with biologist colleagues of his specialized in Proteomics, who have indicated that DNA—while not endemic to non-cellular extrapallial secretions such as nacre and conchiolin (like human hair)—may be found in the form of 'contamination' by extruded DNA from adjacent mantle tissue cells.
Dr. Checa, also a Paleontologist, knows the work of Peter Ward well and relied upon Ward's seminal works on Nautilus biology when researching Ammonoid septal formation in the 1990s. Small world! (And yes, he will also receive bottles of our producer's wine grown near the Cambrian dig depicting Trilobyte Mureriense on the label!)
Now we just need to decide which pearls are to be sacrificed.
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SteveM
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This business about the differing structures of gastropodian and bivalvian nacre is new to this thread, and I believe also to Pearl-Guide. The photos below from a recent Checa/Cartwright collaboration show each type in high magnification. Formation of the gastropodian columnar nacre has to do with biomineral secretion through a porous membrane that serves to protect new nacre formation while the mollusk is fully retracted into its shell?a feature not required in the protected and enclosed environment of a bivalve.
What is amazing?after all the discourse here concerning biomineral duality (nacreous vs. non-nacreous) in Nautilus?is that the nacre of Nautilus should itself be dual, unique among mollusks. This is a subject matter of intense interest to today's nacre scientists, and it should prove magnificently synergistic with ongoing efforts to define the parameters for Nautilus pearls.
The Spirit of Nautilus has much to reveal!
[Bivalve and gastropod nacre growth compared. (A) Oblique view of the terraced nacre of the bivalve
P. margaritifera. (B) Oblique view of the towered nacre of the gastropod Perotrochus caledonicus.]
P. margaritifera. (B) Oblique view of the towered nacre of the gastropod Perotrochus caledonicus.]
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SteveM
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Drs. Antonio Checa and Julyan Cartwright are intrigued with determining the nature of the transition in Nautilus shells from columnar to terraced nacre types. Checa advised me in the course of our recent communications that an absolutely fresh and conserved shell would be imperative, in order to observe the organic membrane involved in the formation of columnar nacre, and that membrane's extent.
I thought one of our more recent shells might prove of interest and set about taking pictures of its inner lining. Among the shots were a few of the shell's Umbilicum, the porcelanous 'plug' most Nautilus shells feature as a covering for their inner whorls.
Ken Scarratt of GIA has pointed to this feature of the Nautilus shell as an example of non-nacreous biomineral secretion, in support of the possibility of non-nacreous Nautilus pearls.
Under the halogen lights, more than a hint of iridescence became evident on the side of the umbilicum that would have been exposed to the mollusk's mantle in the area of its eye.
I have brought this to the attention of the pertinent scientists for comment. It appears to support the occasional conjecture in this thread regarding the possibility of a pearl containing both nacreous and non-nacreous components.
I thought one of our more recent shells might prove of interest and set about taking pictures of its inner lining. Among the shots were a few of the shell's Umbilicum, the porcelanous 'plug' most Nautilus shells feature as a covering for their inner whorls.
Ken Scarratt of GIA has pointed to this feature of the Nautilus shell as an example of non-nacreous biomineral secretion, in support of the possibility of non-nacreous Nautilus pearls.
Under the halogen lights, more than a hint of iridescence became evident on the side of the umbilicum that would have been exposed to the mollusk's mantle in the area of its eye.
I have brought this to the attention of the pertinent scientists for comment. It appears to support the occasional conjecture in this thread regarding the possibility of a pearl containing both nacreous and non-nacreous components.
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SteveM
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Spirit of Nautilus must have classified it as non-sensitive.I can see it!
SteveM
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Peter Ward, a man of few words (except in his very entertaining books), told me: "I know Antonio's work well. He's a genius."
As Checa requires scientific observation of the range of Nautilus mantle movement relative to the shell aperture (in hundreds of years of scientific observation, there is no such specific information), Ward's office aquarium animals may provide the needed subjects.
(Scientific matchmaking by yours truly. I've been promised a ringside seat?)
It appears my ultimate role in this saga is to be the instigator for interdisciplinary work on biomineralization in Nautilus, with an eye on keeping it relevant to solving the mystery of Nautilus pearls.
SteveM
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My recent comments here and elsewhere concerning the improbability of the Nautilus pearls offered in Hubert Bari's 'Pearls' (release September 2010) call for a little review.
What alternative in appearance to round, chatoyant Tridacna pearls might Nautilus pearls provide?
The wildly vortexed non-nacreous pearls I've come across are almost certainly gastropod in origin. Their swirls reflect the spiral/vortexed growth of the shells themselves. As the Nautilus shell borrows key gastropodian features, such structure would neither be foreign to the concept of Nautilus pearls.
The issue of nacreous vs. non-nacreous is mute, given the biomineral complexity ('duality' being far too simplistic) of the Nautilus mantle, as documented in this thread.
The silverish pearl in the post quoted in my previous post offers a possible clue. Purportedly found superficially attached near the aperture of a freshly caught Nautilus shell, it appears to have a thin coating of shell-colored nacre. Micro analysis should help determine the thickness and composition of this layer.
Below are pearls from prior posts that most strongly come to mind when I think of Nautilus pearls. Top row is the infamous pearl reportedly found attached to a dry shell last November, in the form of a button. Bottom row is a pair of amazingly matched teardrops, one found in a cooked Nautilus during its consumption approximately 10 years ago (name, age and island of its finder were provided).
These pearls display a subsurface opalescence, bluish in tint, that suggests alternating biomineral modality. They are distinct from any other known pearl. They are not necessarily beautiful, but that does not diminish their intrigue.
We must now wait for the scientists, or the actual witnessing and documenting of the extraction of a Nautilus pearl from the mollusk. Mysterious that such an incident has not been recorded over the centuries.
'Close' will not win the prize.
What alternative in appearance to round, chatoyant Tridacna pearls might Nautilus pearls provide?
The wildly vortexed non-nacreous pearls I've come across are almost certainly gastropod in origin. Their swirls reflect the spiral/vortexed growth of the shells themselves. As the Nautilus shell borrows key gastropodian features, such structure would neither be foreign to the concept of Nautilus pearls.
The issue of nacreous vs. non-nacreous is mute, given the biomineral complexity ('duality' being far too simplistic) of the Nautilus mantle, as documented in this thread.
The silverish pearl in the post quoted in my previous post offers a possible clue. Purportedly found superficially attached near the aperture of a freshly caught Nautilus shell, it appears to have a thin coating of shell-colored nacre. Micro analysis should help determine the thickness and composition of this layer.
Below are pearls from prior posts that most strongly come to mind when I think of Nautilus pearls. Top row is the infamous pearl reportedly found attached to a dry shell last November, in the form of a button. Bottom row is a pair of amazingly matched teardrops, one found in a cooked Nautilus during its consumption approximately 10 years ago (name, age and island of its finder were provided).
These pearls display a subsurface opalescence, bluish in tint, that suggests alternating biomineral modality. They are distinct from any other known pearl. They are not necessarily beautiful, but that does not diminish their intrigue.
We must now wait for the scientists, or the actual witnessing and documenting of the extraction of a Nautilus pearl from the mollusk. Mysterious that such an incident has not been recorded over the centuries.
'Close' will not win the prize.
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SteveM
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Two more recently-discovered white pearls of 'Nautilus' calibre. Nautilus or (most certainly) naut, they are extremely attractive.
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SteveM
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I replaced my prior photo with two rows of images taken last evening upon receipt of the pearls. They are phenomenal (literally and figuratively), 14.2ct pearl on the bottom row throws two chatoyant rings simultaneously from the dual light sources.
Back to Nautilus:
To share a little suspense, word has reached me of another (hopefully) significant blister find. Diver with shell and crew leader are each flying today from their respective islands to a common airport hub to effect delivery. Hopefully we'll see some images in the next day or two.
Back to Nautilus:
To share a little suspense, word has reached me of another (hopefully) significant blister find. Diver with shell and crew leader are each flying today from their respective islands to a common airport hub to effect delivery. Hopefully we'll see some images in the next day or two.
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