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Man-Made
Gems
The creation o( gems in the laboratory has been a goal
of scientists a entrepreneurs for many years. Today
most of the popular gemstones can be synthesized, that
is, manufactured in a laboratory or factory from chemical
raw materials.
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It
is important to distinguish between synthetics and imitations.
An imitation is a material that has some of the desirable
characteristics of a more costly material. A synthetic
is a man-made duplication of a naturally. ally occurring
substance. |
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One
of the oldest imitation-substitutes is glass. Class has h(
manufactured for thousands of years. Glassmaking was considered
great art by the ancient Egyptians, and Greek and Roman jewelry
studded with glass replicas of gems can be seen in museums.
Even today glass is a widely used and popular substitute for
colored gems such ruby, emerald, and amethyst, and it can
sometimes be effective a attractive. Frequently glass stones
are set with a backing of metallic to The foil reflects light
and creates a far greater brilliance than the glass alone
could achieve. But glass lacks the hardness and dispersion
many natural gemstones, and man has long sought better gem
substitutes.
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Man-Made Gems |
| Man-Made
Gems
One
by one, during the past hundred years, each of
the major gems has been manufactured in the laboratory.
The first to appear were ruby and sapphire, followed
by spinel, emerald, diamond, opal, turquoise ¬and
Chrysoberyl. These synthetic gems are optically
and chemic,3 identical with their natural counterparts.
For example, natural ruby aluminum oxide, colored
red by chromium, that crystallizes in for with
hexagonal symmetry. Synthetic ruby is usually
made by melting aluminum oxide that contains a
trace of chromium.
The resulting crystal has the same internal atomic
structure as natural ruby, as well as the same
optical properties, hardness, and chemical composition.
In fact, the only significant difference between
this material and natural ruby the place of origin:
a laboratory rather than deep within the earth
Fortunately for the gem trade, there are ways
to distinguish between natural and synthetic gems.
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These
are based chiefly on tell-tale intern, markings.
In natural gems there are frequently distinctive
inclusion either gas bubbles, liquid inclusions,
or crystals of other minerals. I synthetics we
find round bubbles, curved growth lines, and various
other markings that reveal the manufactured origin. |
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In
recent years technological developments in the areas of semiconductors
and lasers have required the development of new and special
crystals with useful optical or electronic properties. Some
, 132 these are brightly colored or have other characteristics
suitable for gem use. These new synthetic gems have no natural
counterparts. They are unique laboratory creations that have
extended the world of gemstones in new and unique directions.
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