Nautilus pearls
Nautilus pearls
DrTKStern
Natural Pearl Connoisseur
Senior Guide Member Join Date: Oct 2007
Location: San Francisco, California
Posts: 220
Dear All,
Please see the images on the Nautilus Pearl posting on this section of Pearl Guide.
At the urging of our malacologist, Yolanda Stern, I took a careful fresh look at our collection of Nautilus shells. There are some laboratories tht refuse to consider identifying a pearl as a Nautilus because they say, "A non-nacreous pearl cannot come from a nacreous shell.
The following photographs intend to dispel that notion by showing that the interior surface of a Nautilus pompilius, if untreated, is non-nacreous, and that only beneath it is nacre. Thus there is no problem.
The first photo in the series is a Nautilus pompilius from Celebes Sea, some 8.5 inches at its widest, so mature. The interior of the shell is non-nacreous, though it does have a glow from a deeper layer.
A closeup of the interior shows the non-nacreous layer. It will follow in a second posting.
Best,
Tom
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#220 (permalink) Today, 03:37 PM
DrTKStern
Natural Pearl Connoisseur
Senior Guide Member Join Date: Oct 2007
Location: San Francisco, California
Posts: 220
This is the same shell, but in a close-up of the last portion of the shell. Definitely non-nacreous. Deeper into the throat of the shell, some areas of nacre do show through.
Tom
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#221 (permalink) Today, 03:41 PM
Caitlin
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Location: Southern Arizona
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I love every post on this. I can hardly wait for the definitive word.
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Caitlin
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following the pearl-what a ride!
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#222 (permalink) Today, 03:42 PM
DrTKStern
Natural Pearl Connoisseur
Senior Guide Member Join Date: Oct 2007
Location: San Francisco, California
Posts: 220
With simple abrasive tools available near the Equator, locals polish away the outer non-nacreous layer to expose the beautiful nacreous layer inside. It is probably the thinness of the non-nacreous layer that allows an unusual amount of crystalline formation from the deeper layer to mix in, and that makes the Nautilus pearl the most flamboyant of all pearls.
This photo shows a Nautilus where is has been abraded down to nacre on as many surfaces and the worker can reach. Under a loupe, abrasion marks are easily seen.
Tom
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