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Your Guide to Buying
How to tell if a diamond is real
Tell if a Diamond is Real
Real diamonds are mined from the earth, cut by a professional craftsman
and sold by a known retailer, usually with a diamond certificate from a
known gemological authority.
Fakes are usually cubic
zirconium (CZ) or moissanite
(silicon carbide), or worse, quartz or glass. Many known retailers sell
jewelry with cubic zirconium instead of real diamond and this is fine,
as long as the item is not passed off as real diamond.
Remember, you are the only one who can determine true intent of the
giving, diamond or not, it is the intent that counts.
While some must have a real diamond, others are satisfied with looks
alone. Some diamond alternatives can be very appealing.
best option is to have the diamond appraised by a jeweler you trust,
who can test the diamond without damaging it, but this will cost you.
The following are some things you can do to check for fakes but
remember these are only checks, not foolproof methods. One or more may
eliminate a fake.
for a diamond certificate. When
buying diamonds, a diamond certificate is the best way to make sure you
are getting the real thing. Make sure it's from an impartial diamond
grading authority (e.g. GIA, AGSL, EGL, PGGL) or an independent
appraiser who is affiliated with a professional organization (like the
American Society of Appraisers). The certificate should describe the
diamond and say what the cut, color, clarity and carat weight are. Any
reputable retailer will have the diamond certificate for your diamond
before you purchase it so you can rest assured it is real. In addition,
the retailer should allow you to see, either with a microscope or
loupe, the diamond's described qualities on the certificate so you can
verify the description.
to read a diamond certificate
the Gemological Institute of America is the world’s foremost
authority on diamonds.
Contact GIA 800-421-7250
AGS Laboratories is among the best known and well respected diamond
grading laboratories in the world.
EGL USA is one of the world's premier independent gemological
PRECISION GEM GRADING LABORATORY
through it. Diamonds have a high
"refractive index" (meaning they sharply bend the light that passes
through them). Glass and quartz have a lower refractive index, meaning
they sparkle less because they bend light less, even when they've been
the diamond is not mounted, turn it upside down and place it on a piece
of newspaper. If you can read the print through the stone or even see
distorted black smudges, then it probably isn't a diamond. (Unless the
cut is disproportionate, in that case print can be seen through a real
the stone shows any sign of double refraction, it may be Moissanite
(silicon carbide), a gemstone that is so similar to a diamond that even
jewelers can have a hard time telling them apart. **look at the facet
junctions from the top side of the stone, the 'star' facets' if you see
what looks like double vision then that is the doubling effect.
the diamond is mounted, you should not be able to see the bottom of a
diamond looking directly from the top.
a small dot with a pen on a piece of white paper. Place your unmounted
diamond over the center of the dot. Look directly down on it and if
your stone is not a diamond, you will
see a circular reflection in the
the reflections. A real
diamond's reflections usually manifest in various shades of clear/gray.
If you see rainbow reflections, you're either dealing with a
low-quality diamond or a fake. This is not looking at the diamond, but
reflected light thru the stone on a surface like a white sheet of
the bottom view: Under a
microscope hold the stone table(top facet) down. If you see an orange
flash only to the facets as you rock the stone, it is fake.
a Diamond Tester. These are
readily available and can quickly indicate if it is a true diamond or
the stone. Diamonds are weighed
in carats. 1 carat equals 200 milligrams. Cubic zirconia weighs
approximately 55% more than diamonds for the same shape and size. Use a
carat or gram scale to compare the stone in question to a real diamond.
Scales used are usually electronic (or a triple beam balance scale)
capable of measuring to the hundreth of a carat. Make sure the scale
has been calibrated properly.
the setting and mount. A real
diamond is not likely to be set in a cheap metal. Stamps inside the
setting indicating real gold or platinum (10K, 14K, 18K, 585, 750, 900,
950, PT, Plat) are a good sign, while a "C.Z." stamp will give away
that the center stone is not a real diamond.
the stone under a UV light. Many
(but not all) diamonds will exhibit blue fluorescence under an ultra
violet or black light, so the presence of a medium to strong blue
confirms that it is real. The absence
of blue, however, does not mean it is fake; it could simply be a better
quality diamond. If you see a very slight green, yellow, or gray
fluorescence under ultraviolet light, it may be Moissanite.
it with a heat probe. Real
stones disperse heat quickly and they won't heat up with the probe.
This takes about 30 seconds and is often done free of charge. It also
doesn't hurt the stone the way some other ways of testing will.
the diamond x-rayed. Real
diamonds do not show up on an x-ray, glass, cubic zirconium and
crystals all have slightly radiopaque quailities, diamonds are
a jeweler's loupe to inspect the diamond.
Mined diamonds usually have small imperfections or inclusions that can
be seen this way. Cubic zirconium does not have these imperfections.
For that matter, lab-grown diamonds (which should pass all of the other
tests) usually don't have imperfections either.
the unset diamond in some water.
If it sinks it could be real but if it floats, it is fake.
the stone between your fingers and place in your mouth and exhale on it.
If the stone stays "foggy" for 2-4 seconds, then it is not real. Real
diamonds will have cleared by the time you look at them.
(Be warned though - some jewellers cap cubic
zirconium (CZ) bases with
real diamond which will clear.)
you take the stone for an independent appraisal, expect to pay between
$45 and $85 in the USA, and make sure the stone never leaves your sight
- because they could change or replace your diamond with a fake one of
the same size.
scratch glass, but so do many imitation stones.
a lot of fake diamonds can scratch sandpaper.
your stone registered. Once you know for sure that your diamond is
real, whether through independent appraisal or grading lab, take your
stone to a lab that can register and fingerprint your diamond. This
will ensure you that you have your real stone, and no one will be able
to switch it out without you knowing.
be overly concerned if you cannot tell if the stone is a real diamond.
Even the experts can be fooled sometimes.
is no way to be 100% sure that a diamond is real unless there is a
diamond certificate. If you buy a pawned item, something off a table at
a market, or an item off of a marginal website, you are taking a big
risk and chances are these items are not diamond.
diamonds can be "grown" in a laboratory but they are
still real. They
cost a fraction of what a natural mined diamond costs, but they are
(for the most part) chemically the same as natural diamonds.
the difference between a natural diamond and a synthetic diamond is
best determined by a professional.
to read a diamond certificate
Gold Maple Leaf
Insurance - know before you buy
is Cubic zirconia (CZ) and Moissanite?
Cubic zirconia is a synthetic gemstone that very closely resembles
diamonds. Because of its startling diamond-like appearance and
inexpensive price tag, cubic zirconia is a highly popular gemstone used
most frequently in jewelry such as rings, earrings, bracelets and
pendants. Although cubic zirconia is synthetic, it is inspired by its
natural counterpart, zirconium oxide (ZrO2), first discovered in 1892
but too rare to be commercially profitable. Through a series of
experiments, zirconium oxide and yttrium oxide were eventually melted
together at temperatures reaching 4,982ºF (2,750ºC)
to grow cubic zirconia crystals in the laboratory.
Cubic zirconia is crystalline, flawless, and clear enough to rate a "D"
on the diamond scale for color. Though usually colorless, it can also
be made in nearly any color, including soft yellow, characteristic of
some diamonds. Cubic zirconia sparkles brighter than crystal and is
harder than most gems, making it very durable. It also weighs about 65%
more than diamond.
hardness of a stone - The Mohs scale
Cubic zirconia is softer than moissanite. Diamonds test as a 10 on the
Mohs scale, moissanite is around a 9, almost as hard as diamond while
Cubic zirconia is around 8.25.
Moissanite is said to have more brilliance than cubic zirconia and is
more expensive. CZ is made by melting zirconium oxide with another
metal oxide. Moissanite, however, is a silicon carbide. They do both
exist in natural states but are hard to find.
Moissanite was first discovered in 1893 by a French scientist named
Henri Moissan. Moissanite was introduced to the jewelry market in 1998.
Heating moissanite gradually will cause it to change color starting at
around 150 degrees Fahrenheit. This color change can be diagnostic for
distinguishing diamond from moissanite. Moissanite gemstones are
sometimes marketed under the trademark Berzelian.