Pearl Treatment
While pearl is more often than not a product from
nature, it is difficult to control every pearl are as beautiful and colorful as
we anticipate, therefore, people will use some artificial method to change or
modify the appearance of pearls. Only by this way, the most beautiful sides of
pearls can bring to us. This is very similiar to the process of a jeweler
cutting a raw diamond rocket to get a perfect diamond. Pearl treatements
include:
1. BleachingRemove,
lighten (make whiter) or alter (from dark to light) color by means of chemical
and/ or physical agents or light. This process can make the color look more
even.
2. BuffingRemove
organic residues from the surfaces of natural and cultured pearls following
harvest.
3. PolishingThis
technique is applied to natural and cultured pearls to remove some surface
blemishes and increase luster.
4.
CoatingSpread an artificial layer of substance over the pearl
surface or part of the surface. It aims to change pearls color or improve pearl
luster. Good-quality pearls do not have to be coated to look
lustrous.
5. FillingIf a
pearl is partially hollow or has a loose nucleus, people will fill the void with
an epoxy substance. That will make the pearls more solid and improve their
durability. Fillings can be detected with x-radiographs.
6. IrradiationWhen light color pearls are
bombarded with gamma rays, the irradiated pearls will achieve an iridescent
bluish or greenish gray color. This method work well on freshwater pearls and
can be used with dyeing.
7.
OilingOiling is also used to improve pearl luster.
8. DyeingAny color caused artificially
by the application of a dye to pearls can be call dyeing. Dyeing is the most
often used technique to get colorful pearls that people want. Dyed pearls are
not fakes, but people can get them much easier than pearls of natural color.
They fulfill people¡¯s desire of special fashion in different occasions while
cost less. For their soared price, few people can afford natural black or golden
pearl, treated pearl is undoubtedly a great invention to fit different tastes
and trends.
Maybe you still want to know which is dyed and which is
natural and make the final decision. There is some tests Shecy can provide to
help:
Price testSome types of true color pearls are typically
expensive, e.g. Tahitian pearl, Golden South Sea pearl, Akoya pearl with Rose
overtone (Hanadama pearl). If the price is unbelievably low and the merchant
doesn¡¯t own a special reason for this price. The pearls are probably
treated.
Size testIf a
pearl¡¯s diameter is smaller than 9mm, and is marked as Tahitian pearl or Golden
South Sea pearl, that must be false color. For almost all Tahitian and South Sea
pearl, expect for their Keshi pearls, are larger than 9mm. Akoya oysters, on the
other hand, can only produce a wide range of pearls below 9mm.
Drilled-hole testLook at the drilled hole of a pearl. If
the nucleus looks dark and nacre inside looks white, the pearl is dyed. The
other clue that indicates dyed pearl is dye concentrating around the drill hole
or on some spot of pearl surface.
Color
testObserve the pearl color carefully. Any of the following clues
would indicate whether the pearl is dyed or not.
Dyed color can be dark to
black, and without natural overtone.
As a creature of nature, The true color
pearl differ from one to the other, if all the pearls in the piece look the
exact same color, the pearls are dyed
Magnifier
testExamine the surface of the pearl with a magnifier or loupe. If
the color in or around the blemishes is stronger and more intense than the rest
of the pearl, this pearl is dyed.