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, simulant and synthetic gems.
While occasionally used to deceive even the most experienced eyes, most simulant and synthetic gems are honestly used in a wide range of applications ranging from inexpensive costume jewelry to radio components and watch bearings.
The gem trade draws slight distinctions between simulants and synthetic gems based on whether they have exactly the same properties of the material they are trying to imitate.
Simulants are artificially made materials that are sufficiently close in appearance to other more costly gem materials that they provide superficially convincing substitutes. Common examples include substituting White Cubic Zirconia and Moissanite for Diamonds or substituting Synthetic Blue Spinel or Blue Topaz for Aquamarines.
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 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 it’s 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 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 man-made jewel and is the only totally worthy Diamond substitute. While considerably less expensive than Diamond, it is expensive in comparison to other man-made gem materials and therefore included as a Semi Precious Gem at Thaigem.com.
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, synthetic or simulant material. Color usually derives from one component only or sometimes from dyes within the junction 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.
“Synthetic” is a term that is commonly used to describe anything which is synthesized or artificially produced. In the gem trade, synthetic gems are artificially made materials that possess exactly the same composition and structure as their natural counterparts. A variety of methods are currently used in the production of synthetic crystals, resulting in different qualities, appearances and prices.
The Flame Fusion or Verneuil Process
This is 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 synthetic 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 synthetic 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.
Synthetic and simulant are terminology used by the USBM for laboratory grown gemstones. Others in the gemstones industry may use different terms to refer to laboratory grown gemstones. Laboratory grown synthetic gemstones have essentially the same appearance and optical, physical, and chemical properties as the natural material that they represent. Synthetic gemstones produced in the United States include blue Sapphire Oval, coral, diamond, emerald, garnet, lapis lazuli, quartz, ruby, sapphire, spinel, and turquoise. Laboratory grown simulants have an appearance similar to that of a natural gemstone but have different optical, physical, and chemical properties. The gemstone simulants produced in the United States include coral, cubic zirconia, lapis lazuli, malachite, and turquoise. Additionally, certain colors of synthetic sapphire and spinel, used to represent other gemstones, would be classed as simulants. Colored and colorless varieties of cubic zirconia are the major simulants produced.
Techniques for making synthetic gems include flux methods for Emerald, Ruby, Sapphire, Spinel and blue Sapphire Oval.
The other method is the hydrothermal method, often used for growing Beryl (Emerald, Aquamarine, and Morganite) and Quartz.
Our LAB Gemstones are produced by the flux method (if not other mentioned), some fine LAB Emeralds are produced by the hydrothermal method.