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(Let The Buyer
Beware)
Purchasing gemstones while traveling overseas is
a very tempting, cost savings idea. If you
do your homework, you could theoretically get a
good buy, again if you do your homework.
What usually happens is a traveler is lured into
jewelry store by an unsavory cab driver or
someone paid by a jewelry store to get travelers
into their store. Many of the scams seem
to be reported coming from countries such as
India and Thailand, and Bangkok, but the scam
could occur anywhere.
The scam continues by you being enticed by
being told you can purchase "stones"
at very low prices by being taken directly to
the manufacture of the jewelry, or the person
who supplies the jewelry stores in the tourist
areas. Once you arrive at the location you
are taken into a room where you observe precious
stones being polished and made into jewelry.
At that point you are taken into a room where
you are shown various precious stones or jewelry
pieces containing precious stones. The
prices seem outstanding and you make a purchase
of a few "Oriental Emeralds"
When you arrive home, show you new jewelry to
your friends, and everything ends happily ever
after, until you take the jewelry into the local
jeweler to have it cleaned or to have the loose
precious stones mounted. That's when you
find out your "Oriental Emeralds" are
actually "Green Sapphires" worth about
one quarter of what a true emerald is worth.
What you really purchased was in fact a fake,
phony gemstones, synthetics, glass
imitations, natural substitutes, enhanced
(treated) gemstone, or "reconstituted
gems." No mater what you called them,
you were ripped off..
Within the United States, it's a violation of
Federal Trade Commission guidelines to use names
of gemstones which mislead buyers as to the
identity of what they are buying. This is often
not the case abroad. When shopping overseas you
might be tempted to purchase stones from a
jewelry store and not know in reality that your
are buying a worthless stone. Below is a
partial list of misleading gemstone names
encountered abroad, but represented as expensive
gems.
For explanation of how and why gems are
altered see information following the below
misnomers.
Misnomers (and what they really
are)
- Japanese Amethyst - Synthetic Amethyst
- Alaskan Black Diamond - Hematite
- Herkimer Diamond - Colorless Quartz
- Matura Diamond - Colorless Zircon
- Mogok Diamond - Colorless Topaz
- Ranggon Diamond - Colorless Zircon
- Chatham Emerald - Synthetic
- Gilson Emerald - Synthetic
- Oriental Emerald - Green Sapphire
- Goldstone - Glass with Copper Crystals
- Australian Jade - Chrysoprase Quartz
- Indian Jade - Aventurine Quartz
- Korean Jade - Serpentine
- Manchurian Jade - Soapstone
- Mexican Jade - Dyed Green Calcite
- Soochow Jade - Serpentine, Soapstone
- German Lapis - Dyed-Blue Jasper
- Swiss Lapis - Dyed-Blue Jasper
- Atlas Pearl - Imitation
- Red Sea Pearl - Coral
- Adelaide Ruby - Garnet
- Australian Ruby - Garnet
- Balas Ruby - Spinel
- Bohemian Ruby - Garnet
- Brazilian Ruby - Tourmaline
- Cape Ruby - Garnet
- Lux Sapphire - Iolite
- Water Sapphire - Iolite
- Madeira Topaz - Quartz
- Palmeira Topaz - Quartz
- Rio Topaz - Quartz
- Smoky Topaz - Smoky Quartz
What does the term "synthetic"
gemstone really mean?
A "synthetic" gemstone
is laboratory-grown, or manufactured. All the
chemical, physical, and optical characteristics
of synthetic gemstones are identical to their
natural counterparts. Good synthetics have been
made since the early 1900s. Because they mimic
natural stones so well, most synthetics are
difficult to detect, even by experts. Often, the
only clue is the physical perfection of the
stone--synthetics are usually flawless.
Which are the most well-known gemstone
imitations?
Imitation, or simulated, gemstones may be
natural (substitutes) or manmade (artificial).
Substitutes are cheaper look-alike stones.
Red spinel or garnets may be substituted
for ruby, and green tourmaline is used to
replace emerald. Cubic zirconia, a manmade
stone from a natural substance, is a
well-known substitute for diamond.
How can we tell?
Their name is often a clue to
substitutions. Genuine gemstones are called by
their true names, with no descriptive words as
part of the name.
Example, a sapphire is simply called a
sapphire. However, a water sapphire is iolite
or cordierite. A balas ruby is spinel. A
Madeira topaz is citrine. Evening emerald may
be any green stone. German lapis is dyed
chalcedony. Mexican jade is dyed onyx.
Herkimer diamonds are quartz.
New names are invented on a regular basis.
As a consumer, you need to be aware that
gemstones with additional names are
substitutes and pay the appropriate price for
them.
What about imitation stones made of glass?
Glass is a time-honored material for making
artificial gems. Glass imitations have been
found in Egyptian tombs which are at least
5,000 years old. Non-transparent glass was
first used to make artificial turquoise, lapis
lazuli, and onyx.
Artificial gemstones of all varieties were
later made from paste, which is a very hard
kind of transparent glass. Glass is often used
now to make artificial jade and opal. The
"fabulous fakes," which are nearly
always glass, allow us to make many pieces of
beautiful, but inexpensive, costume jewelry.
Is plastic common in imitation
gemstones?
Plastic is also frequently used for
imitation gems, particularly the organic ones
like amber, ivory, and coral.
What is a natural
gemstone?
Suppliers may only call
gemstones natural if nothing has been done to
them which changes their color, stability, or
durability. Natural gemstones may only be
polished or cut to show off their beauty.
Natural stones often have imperfections in
them. Perfect gemstones are a tip-off to
experts that a human has improved upon Mother
Nature.
What are the main reasons for
changing a natural gemstone?
Many gemstones are enhanced,
which may improve or change the color, provide
stability, or increase durability. Stability
means that the stone won't change under normal
conditions. Turquoise is an unstable gemstone
in its natural state, because chemicals and
body oils easily damage it. Durable stones
won't scratch or break when worn. Soft stones,
like opal, must be protected if they are to
last.
How are gemstones changed?
The four main methods of
enhancement are heat treatment, irradiation,
chemical treatment, and assembly. While some
enhancements are done with an intent to
deceive, many gemstones would not be usable in
jewelry if they were not treated in some way.
Reputable suppliers disclose known
enhancements at the time of purchase.
Except for durability
enhancement, what other reasons are there for
chemically changing gemstones?
The results of heat treatment
and irradiation often mimic what Mother Nature
would have achieved had the stones been left
in the ground a few more centuries.
How can we tell the
difference between a natural and an
"enhanced" (treated) gemstone?
It is usually impossible to
detect which gemstones have been enhanced by
either of these methods. Chemical enhancements
are generally used to change the surface
characteristics of gemstones, and assembly is
often used to protect fragile stones.
Assembly is usually easy to
detect before a stone is set; the results of
chemical treatments range from obvious to
invisible.
What is heat treatment?
Heat treatment is commonly
used to improve color. Color changes resulting
from heating are permanent in most gemstones.
Amethyst, ruby, sapphire,
topaz, tourmaline, and zircon all are
routinely heat-treated. Most aquamarine now
sold has been heated, to change it from its
natural green to the blue that is currently
popular.
What about irradiation?
Irradiation is also used to
change or deepen gemstone colors. Clear topaz
is irradiated to produce blue topaz, and
colorless tourmaline may be changed to any one
of several colors. Some diamonds are
irradiated to improve their color.
Irradiation is not always
permanent; some irradiated stones revert to
their natural colors when exposed to extreme
heat or light.
What does chemical treatment
do?
Chemical treatment of
gemstones includes bleaching, dyeing, and
staining. It also includes the uses of oils,
waxes, resins, or plastics to stabilize or
change the appearance of a gemstone.
Chemical treatments are often
called impregnation because the chemicals
usually penetrate the surface of the stone.
Porous stones, like turquoise, are frequently
sealed with wax or resin to keep the color
from fading.
Oils, waxes, and plastics are
used on many stones to hide small scratches
and surface flaws. Coral, ivory, and pearls
may be bleached.
Nearly all gemstones can be
dyed or stained. Some chemical treatments are
permanent. Others will dissolve in solvents
like acetone or in ultrasound cleaners. Waxes
melt when exposed to heat or strong light.
Bleaching can be impossible to detect. Dyeing
can usually be detected with a microscope.
What does
"assembly" mean?
Assembled stones may be
composites like doublets and triplets, or they
may be foilbacks. A composite stone is two or
three pieces of material fused or joined by
colorless cement.
Although any stone may be made
into a composite, opals are the best-known. An
opal triplet consists of a piece of good opal
sandwiched between a top layer of clear quartz
and a bottom layer of low-quality opal. A
doublet is usually a good opal underneath a
quartz layer. The quartz helps protect the
delicate opal.
Composites also allow the use
of gemstones too small to be used otherwise.
False composites contain no gemstone material.
False opal doublets are made from crystal
cemented over abalone shell. Soude emeralds
are crystal cemented over green glass.
What does foilback mean?
Foilbacks have been made for
nearly 4,000 years, using a variety of
techniques. One kind of foilback involves
placing a backing of foil or a metallic
coating on a stone to give it a more brilliant
color.
Colored substances on
foilbacks add color to clear stones or deepen
the color of pale stones. Cat's-eyes and star
effects are created with etched backings.
Rhinestones are one example of a popular
foilback.
Are pearls synthetic or
natural?
Cultured pearls fall into a special
category. Natural pearls are made by mollusks
(oysters and mussels). Mollusks have shells
and most of them live underwater. They secrete
a substance called nacre (rhymes with acre).
The purpose of nacre is to make the inside of
the shell smooth so that it doesn't irritate
the soft body of the mollusk.
A pearl is simply an abnormal growth of
nacre. Natural pearls are formed when
something, such as a grain of sand, gets
inside its shell and irritates the mollusk. To
reduce the irritation, the animal covers it
with thousands of smooth layers of nacre. The
process is similar to what your body does when
it forms a callus to protect irritated skin.
The difference between cultured and natural
is in how the pearl is started. A cultured
pearl is formed around an irritant placed in
the oyster by humans, rather than around a
grain of sand randomly lodged in the oyster by
nature.
The outsides of natural and cultured pearls
have an identical appearance. It generally
takes an expert and special x-ray equipment to
distinguish cultured from natural.
Cultured pearls may not be sold as natural;
however, they are regarded as "real"
pearls and not fakes. Nearly all pearls on the
market today are from Japan. There are also
many pearl companies in Hong Kong. Freshwater
pearls are also produced in the United States.
In Tahiti, the famous black pearls are
cultured.
How are imitation pearls made?
Fake pearls have been made for more than
400 years. Fish scales are used to prepare a
substance called pearl essence. The essence is
used to coat glass or plastic beads to
manufacture artificial pearls. A thick coating
of pearl essence can make the fake look very
realistic.
Fake pearls are easy to detect. They feel
smooth if gently drawn across the edge of your
teeth. Natural and cultured pearls feel gritty
or rough.
What does "Reconstituted" mean?
Reconstituted gems fit into a separate
category. Although reconstituted gems do
contain genuine material, experts regard them
as imitation.
Reconstituting, or reconstructing, means
that small fragments of gem material have been
combined to form a large piece. Amber and
turquoise are two common examples.
Reconstituted amber, typically called
ambroid or pressed amber, is made from scraps
and shavings generated by amber carvers. The
tiny pieces are collected and heated, then
pressed into large blocks. Manufacturers of
ambroid can easily insert insects to make it
look even more like natural amber.
Reconstituted turquoise is made from
inferior grades of turquoise that have been
powdered. The powder is mixed with an adhesive
and dye mixture to form a solid mass, which is
then cut into shapes.
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