How to distinguish a genuine gem from a fake

How to distinguish a genuine gem from a fake

By Roland M. Sutrisno

JAKARTA (JP): People often say that two grams of a precious
stone can be exchanged with two truck-loads of gravel or river
pebbles. Precious stones or gemstones are so valuable that they
easily command high prices.

We therefore need to pay special attention to the gemstones we
usually wear. A gemstone may be a heirloom, a gift from a friend,
an intimate friend, a find from a river or a railroad track; it
may come from a sidewalk booth, a plaza or a mall. It is
important that we know the difference between a natural gemstone
and a synthetic one. The majority of precious stones now in
circulation (nearly 60 percent) are imitation or synthetic ones,
says gemstone expert Sam Han Kay.

Indeed, synthetic stones are beautiful to the eye. They are
usually made from natural stones through a chemical process which
involves a temperature of several thousand degrees, an
application of striking colors, and polishing here and there. The
result is gemstones carrying a luster of beauty and distinction.
Synthetic stones are manufactured by a processing machine aided
by laser rays to yield the colors desired by a purchaser. The
resulting colors are perfect.

Imitation stones have an even wider circle of users due to
their attractive lower prices. These stones are indeed made of
varied colors of glass or perfume bottles which have been
liquefied, and are molded in such a way as to take a form that is
"genuine".

Now, having read this article you must be prepared for a heart
attack. In other words, do not be startled if a so-called genuine
gemstone you are wearing is a fake and is just plain glass. How
to distinguish the genuine gem from the fake one?

It is certainly not difficult to recognize a genuine precious
stone if you are used to looking at it. For a layman, however, it
is indeed very hard to tell the difference between a genuine and
an imitation stone. It may happen that the stone is natural but
its colors have been processed, creating brilliant colors, even a
"star".

Characteristics

The following are the characteristics of a genuine stone:

1. Natural veins: Existing lines in a transparent stone. The
natural lines look to us exactly like veins, only they appear as
fine as hair. To have a better look you can use a 10- or 20-fold
magnifying glass. You may also resort to a microscope.

2. Form: From its form we can see if the underpart is rough or
as smooth as molded work. If it is smooth, it is nearly certain
that the stone is an imitation or glass, because a fake stone has
a perfectly neat basis that a genuine stone does not possess.
Moreover, the underpart of an imitation stone is somewhat
concave. A genuine stone has a rather rough undulated underpart.
The smoothness of a stone is certainly the result of scouring,
either by machine or abrasive paper.

What about stones cut into the form of diamonds, while the
upper part is round or flat? This form is rather difficult to
distinguish. We can give proof by another method.

3. Bubbles in stones: We can find the characteristics of genuine
stones by the bubbles inside the stones. They are visible under
the naked eye or with a 10- or 20-fold magnifying glass.

Another aspect requiring our attention is that the edges of
the bubbles in the stones are dented and not even. This is
clearly visible when we compare genuine stones with imitation
ones.

A word of caution, though, to those wanting to use a
magnifying glass in front of a jeweler. He may be angered at
someone inspecting his merchandise with a magnifying glass. He
could be offended if the genuineness of his stone is doubted.

If the stone is an imitation, smooth bubbles with even edges
will almost certainly be seen. If it is still difficult to see
the difference, compare the imitation stone with some clear glass
at home. There are stones showing no bubbles at all, even when
viewed with a 20-fold magnifying glass. In that case we have to
use another method.

4. Colors: If a magnifying glass does not show any bubbles in a
stone, we look for the most dominant color. If the color is
brilliantly and radiantly clear, and attractive, we can guess
that the stone is genuine, although it is only lit by natural
lighting and not by a focused light or a flashlight. What about
the cut underpart of the stone like a diamond? It can be
differentiated if the stone emits rays and the colors in it are
uneven. The color appears like a gradation. A magnifying glass
clearly shows it. It is sufficient to use a 10-fold magnifying
glass.

What about non-transparent stones? We can tell the difference
from the colors. The important thing is that the stone reflects
light even when only given a cursory rub. If you are used to
seeing gemstones or jewels you will see the difference.

In case of an imitation stone, its colors will look like added
colors to jelly or candy. However, it will be very hard to rely
on the criteria of color, because some kinds of stones look
exactly like candy. Topaz is yellow or white, emeralds are green,
rubies look like FOX candy. So, the criteria for colors to
inspect the genuineness of stones are nearly impracticable as the
best guide.

5. Veined: A genuine stone will appear veined if we hold it in
sunlight or if we put a light underneath it. An imitation will
certainly not show veins. The veins appear naturally over a
period of millions of years and are the result of the stones
being deep in the earth.

6. Misty: A genuine stone will clearly show some mist like a
cirrus or cumulus clouds with graded colors. If a stone shows a
lot of mist or cloud it is fairly certain that it is genuine. An
example is a stone with much mist such as the amethyst which is
violet.

7. Chicken feathers or insect wings: A genuine stone looks like
it has a chicken feather or an insect wing floating in the stone.
This can be seen in the blue sapphire or the clear and
transparent ruby.

8. Refraction of a stone: The refraction of a genuine stone can
be tested with a refractometer which tests the light reflected by
natural stones.

9. Diamond Tester: It is different with diamonds. An instrument
to test whether a diamond is genuine or not is the Diamond Tester
which, upon contact with a diamond, will give a sound even with
the ugliest and cheapest diamond. This instrument tests diamonds
only and not other gemstones.

10. Emerald Telescope: The telescope to test emeralds is
especially designed to test emeralds and is equipped with a
special filter. It readily shows whether the emerald is genuine
or fake. A genuine green emerald will look red with the
telescope. A fake emerald will remain green.

11. Feeling: The most important factor and one that is a human
aspect is feeling. If we are used to looking at stones, every
day, every hour, every minute, we can certainly tell the
difference immediately. A stone will "speak" to us, whether it is
genuine or fake. This factor is very hard to describe in detail
and extensively. If we know genuine stones closely by continuous
investigation, a feeling will gradually grow to discern the
genuine from the fake.

Let us not lose courage if the stones we wear are imitations.
Perhaps the element of subjectivity makes us happy. If we are
happy with the stones we wear, especially if they are heirlooms,
we need not lose heart.

Once again, spiritual satisfaction is a very important factor.
Whether you use genuine or imitation stones, it is up to you or
to your pocket.

-- Roland M. Sutrisno is collector of precious stones