Tom, thanks for posting the image, a higher resolution than posted earlier in the thread it would seem.While there have been doubters, Steve Metzler's find of a nice blister Nautilus pearl should reassure them that Nautilus can in fact make pearls. The photo attached was taken by the Van Pelt Studio in Los Angeles. The pearl has been certified by GIA as a Nautilus pearl.
For those of you new to this thread, we knew from historical records of the Sultanate of Sulu and North Borneo that on less than 10 occasions in the past three centuries, Nautilus pearls were presented to the Sultan by his people. We suspect they come not from Nautilus pompilius, but from Nautilus suluensis, a smaller but otherwise identical animal roaming the depths of the Sulu Sea.
Tom, thanks for posting the image, a higher resolution than posted earlier in the thread it would seem.
Validity of the GIA certification continues to rest on obtaining consensus with the European labs. [/I].
Nope...I'll go with GIA and the man who looked at 700,000 pearls a year for a decade or more.
The burden in my view is to disprove GIA, not the reverse. You and I both know Nautilus pearls exist, and that all of the elements for formation exist in the animal. I know where our Nautilus pearl came from and for a second pearl have the actual shell.
Respectfully,
Tom
All living organisms produce concretions that may or may not be called pearls according to local custom—that Nautilus would produce such has never been in doubt! And I do not doubt that the pearl in your prior post is Nautilus, nor any number of my own. But we must be objective.I'll go with GIA and the man who looked at 700,000 pearls a year for a decade or more.
The burden in my view is to disprove GIA, not the reverse. You and I both know Nautilus pearls exist, and that all of the elements for formation exist in the animal. I know where our Nautilus pearl came from and for a second pearl have the actual shell.
It was Peter Ward and his co-researcher Bruce Saunders that ultimately clarified Nautilus taxonomy, with the help of modern molecular biology, in 1997. Turns out, there is Nautilus?and Allonautilus (Ward and Saunders, 1997) (previously known as Nautilus Scrobiculatus). Just two genera and a grand total of about five species?all that remains of Nautiloidea, together with Ammonoidea, one of the most dominant and durable classes to ever roam the face of the earth.Nautilus suluensis -- very interesting.
5. Mantle; Shell; Nuchal membrane.
The integument of the visceral sac has always been reckoned as part of the mantle on account of the fact that the whole of the mantle area is capable of secreting nacreous substance externally, the posterior or visceral portion in particular being concerned with the formation of the septa. The growth of the shell takes place at the free border of the pallial fold, but the whole outer surface of the fold can deposit nacre, as is indicated by the occasional appearance of nacreous intumescences on the inner surface of the shell, and also by the rare occurrence of the phenomenon of true pearl-formation, one example of which came under my observation.
Upon taking a shell, of which the animal had died and fallen out, from a basket at Lifu, something rattled like a stone in the shell. It turned out to be a handsome pearl of large size, but of doubtful value as a gem, since the shape is not quite regular, flattened on one side, and the surface is not absolutely pure. It measures about (XX) millimetres in major diameter, (XX) mm. in height, weighs (XX) milligrammes and is, I believe, the first nautiline pearl to be recorded.
I had sought it for some time and noticed on a couple of occasions some tattered copies at used booksellers for literally hundreds of dollars. In recent days a Nautilus scientist I had not previously contacted mentioned the pearl reference somewhat tongue-in-cheek (apparently the attitude de rigueur among scientists regarding these paragraphs for most of the past century), causing my renewed search. As it happens, on August 31, 2010, Smithsonian Institution had donated a copy to the Biodiversity Heritage Library, and it is now in the public domaine. 46 downloads have occurred as of today.Is Willey's work in a book form?