Is there a way to know how thick is the nacre layer in a cultivated
pearl?
Thanks!
Is there a way to know how thick is the nacre layer in a cultivated pearl?
Without X-ray it would require experience.
Thick nacre is very shiny and has aura of color different from pearl
itself. But beware of coatings which can simulate it.
Like I said, experience is everything. If great deal of money is
involved, X-ray is mandatory.
Leonid Surpin
Is there a way to know how thick is the nacre layer in a cultivated pearl?
Using magnification, look down the drill hole. That will give you a
bit of an idea.
Elaine
CreativeTextureTools.com
Generally, if you look at a pearl you can tell if the nacre is thick,
but to know exactly how thick think you can x-ray the pearls.
Yup. Drill into it. Then look with a loupe.
Have fun and make lots of jewelry.
Jo Haemer
timothywgreen.com
Is there a way to know how thick is the nacre layer in a cultivated pearl?
If the pearl is drilled, look at the hole under magnification.
Jerry in Kodiak
One less scientific way to judge thickness of the nacre on a
cultured pearl (and its overall quality) is to spin it in direct
light and look for uneven reflections from the mother of pearl bead
it was formed around. A pearl with thick nacre will show none or
almost no “blinking” as it is turned, while one with thin nacre will
blink like a lighthouse.
If it is a strand of cultured pearls, hold it with one end in each
hand and twist the entire strand so as to rotate all of the pearls.
In the case of a single loose pearl, roll it back and forth in a
trough of some kind, folded paper works well.
The opacity of the nacre in addition to its luster, orient and color
is more important to a cultured pearl’s overall quality and value
than the thickness, although the two generally go hand in hand.
Dave Phelps
Is there a way to know how thick is the nacre layer in a cultivated pearl
Without X-ray it would require experience. Thick nacre is very
shiny and has aura of color different from pearl itself. But
beware of coatings which can simulate it. Like I said, experience
is everything. If great deal of money is involved, X-ray is
mandatory.
A strong single point light source with a polarising filter will
give you agood idea as the material underneath will invariably be
made of MoP shell and have an lamination orientation which will show
up well in the polarised light. You will need to turn the pearl to
get the best orientation and then all will become apparrent. The
nacre will show up well against the layers of the “seed”.
Nick Royall
Is there a way to know how thick is the nacre layer in a cultivated pearl
In addition to Nick’s fine suggestions, if the pearl in question is
drilled or half drilled, AND you can see a bit into the drill hole
(such as with strung pearls, you can pull the thread slightly to the
side, and with a loupe examine the inside of the hole near it’s top),
then you can simply see how thick the nacre layer of the pearl is.
The nacre layer looks distinctly different from the underlying mother
of pearl bead, and there is usually a slightly darker thin line
separating the two, so you can easily see how thick that nacre layer
is right there at the drill hole. It may vary over other parts of the
pearl, but this is usually a pretty good idea for the overall
thickness. If the pearl is not drilled, or you cannot access the
drill hole, then ignore this, and go read Nick R.'s post again. 
Peter Rowe