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Created
& Simulated Gemstones
Introduction
The desirability and high value of gemstones has long meant that some gems
are unobtainable for many people. Filling the gap for their demand, are the
almost identical looking but inexpensive substitutes, created and simulated
gems.
While occasionally used to deceive even the most experienced eyes, most created
and simulated gems are honestly used in a wide range of applications ranging
from fashion jewelry to radio components and watch bearings.
The gem trade draws slight distinctions between created and simulated gems
based on whether they have exactly the same properties of the material they
are trying to imitate.
Created Gemstones
Created Gemstones are identical to their natural counterpart in every way
(i.e. hardness, composition, optical properties etc.); the only difference
is that they are created in a laboratory not in nature. For example, created
Sapphires are made of Corundum, the same base mineral as natural Sapphires,
and have essentially the same optical, physical, and chemical properties as
natural Sapphires.
Created Gemstones are also known as “laboratory grown”, “laboratory created”,
“[manufacturer name] created” or “synthetic” Gemstones. Technically, no created
gemstone is rare, as they can be made anytime.
A variety of methods are currently used in the production of created crystals,
resulting in different qualities, appearances and prices.
The Flame Fusion or Verneuil Process
This
was the first process used for gemstone synthesis and is still extremely common.
With low production costs and high crystal growth rates, large numbers of
flame fusion gemstones are readily available. It is the most inexpensive crystal
production method and offers very good value for money. Consequently, it is
also used to make the majority of created Rubies, Sapphires and Spinels.
The method utilizes the powdered ingredients of a gem by fusing them together
under a high temperature oxy-hydrogen flame. The ingredient powder melts and
crystallizes in successive layers. This method fortunately leaves us a wealth
of clues regarding its manmade origin. Important identification features are
curved growth layers resulting from crystallization in layers. While best
observed under a 10x loupe or microscopic, very often these curved layers
are visible to the naked eye. Often present too, though slightly harder to
see, are gas clouds containing rounded bubbles of trapped gas, an inclusion
very rarely seen in natural gems.
Trapped gas bubbles are clearly visible in this Created Flame Fusion Blue
Sapphire - trapped during synthesis; these bubbles are not seen in natural
origin Ruby and Sapphire.
Flux-Melt Technique
This
is a high quality gemstone synthesis technique rarely used in fashion jewelry
or industrial applications due to higher production costs. These synthetics
pose the greatest threat to the gem trade as flux grown Rubies have inclusion
patterns that very closely mimic natural fingerprint patterns seen in natural
Rubies.
Molten fluids or fluxes are used to manufacture flux-grown gemstones. By dissolving
gem-producing ingredients in the fluid and then crystallizing them under controlled
conditions to produce the desired gem mineral.
While the physical properties of natural and flux-grown gems are the same,
the clues to their synthetic origins are usually found on the microscopic
level. Small, often hexagonal platelets from the side of the platinum crucible
are proof of synthetic origin. Also seen are flux fingerprints that have powdered
residues within the fingerprint cavities.
The Hydrothermal Technique
Commonly used in manufacturing high quality synthetic hydrothermal Emeralds,
this process closely mimics how many crystals in nature originate from high
temperature, high pressure water solutions.
The ingredient materials are enclosed in a partially filled, sealed container
of water. Heated to high temperatures the feed materials are dissolved and
at point of cooling crystal growth is induced.
Simulated Gemstones
Simulated Gemstones don't have the same properties (i.e. optical, physical,
and chemical etc.) as natural gemstones but resemble the natural gemstone
they imitate. A simulated gemstone can be any material that takes on the appearance
of a natural gemstone. Even obvious imitations such as glass or plastic can
be accurately described as simulated gemstones.
However, please be aware that a created gemstone can be described as either
a created gemstone or a simulated gemstone depending on how the material is
marketed. For example, purple corundum (the base mineral of both natural and
created Sapphires) can be created in a laboratory and called “Created Purple
Sapphire” or used to resemble purple Quartz and called “Simulated Amethyst”.
As another example, color change corundum (the base mineral of both natural
and created Sapphires) can be created in a laboratory and called “Created
Color Change Sapphire” or used to resemble color change chrysoberyl and called
“Simulated Alexandrite”.
Another example of simulated gemstone is Cubic Zirconia or CZ, marketed as
a Diamond simulant under a variety of brands names. Cubic Zirconia resembles
Diamond but does not have the same properties as Diamond. While a number of
Diamond simulants exist on the market, only Cubic Zirconia and Moissanite
have any commercial significance. Although man made artificial products, they
are commonly used use in the jewelry industry.
Cubic Zirconia
Cubic Zirconia is a very inexpensive Diamond simulant and an excellent alternative
to Diamond. Although mostly seen in its white or colorless forms, CZ (as it
is commonly known) is also available in a wide variety of colors. Nearly as
hard as Ruby and Sapphire, the optical properties are high and CZ has good
brilliance. Despite its near stranglehold on the Diamond simulant market for
the last two decades, the introduction of the superior Moissanite has knocked
CZ a long way back into second place.
Moissanite
Moissanite is a very hard and brilliant jewel manufactured by man. Found naturally
in asteroids and meteorites, scientists only started manufacturing Moissanite
as gem simulant fairly recently.
Showing even more fire than a Diamond, Moissanite is like no other manmade
jewel and is the only totally worthy Diamond substitute. While considerably
less expensive than Diamonds, it is expensive in comparison to other manmade
gem materials.
Moissanite is a synthetic that provides the gem trade with the best of both
worlds. To the naked eye, Moissanite is virtually indistinguishable from Diamond.
Under a 10x loupe it is quite easy to distinguish from Diamond due to its
heavy double refraction, manifesting as the doubling of facet edges.
Composite Gemstones (Doublets)
Known
as doublets or triplets, these gemstones consist of two or more parts that
have been artificially joined together to give the impression of a single
gemstone.
The component pieces of composite gemstones include combinations of natural,
created or simulant material. Color usually derives from one component only
or sometimes from dyes within the layers.
Composite gemstones are most realistic if natural gem material is used for
the crown of a faceted gem, as casual inspection reveals natural inclusions.
Pictured here is a Ruby Doublet with a natural Sapphire crown joined to a
synthetic Ruby base, giving the appearance of a large Ruby with natural inclusions.
Clearly visible is the junction where the two parts meet.
Popular Doublets include Ruby Doublets, Sapphire Doublets and Alexandrite
Doublets. These should not to be confused with the doublets seen in Amber,
Opal and Ammonite as these are constructed only to provide an otherwise fragile
gem material with strength.
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