Synthetic and Imitation Rubies
There is a real difference between synthetic and imitation rubies.
Synthetic gemstone are not imitations of real gems, but are an actual creation, by artificial means, of a real gemstone so that the product is identical, chemically, physically and optically, with the one found in nature.
The terms synthetic, laboratory-created, and man-made are all pretty well synonymous. Diamonds, ruby, sapphires, opals, and emeralds that have been manufactured in labs and which possess very nearly identical chemical and physical characteristics to the genuine article. Are called synthetic corundums. Synthetic corundums, including ruby and sapphire, are very common and they cost only a fraction of the natural stones. Smaller synthetic diamonds have been manufactured in large quantities as industrial abrasives for many years. Only recently, larger synthetic diamonds of gemstone quality, especially of the colored variety, have been manufactured.
Synthetic rubies have been made since the late 19th century. They have become more common since the work of Auguste Verneuil and the introduction of the flame fusion process. Other processes in which synthetic rubies can be produced are through the Pulling process, flux process, and the hydrothermal process. Most synthetic rubies originate from flame fusion, due to the low costs involved. Synthetic rubies may have no imperfections visible to the naked eye but magnification may reveal curves striae and gas bubbles. The fewer the number and the less obvious the imperfections, the more valuable the ruby is; unless there are no imperfections (i.e., a “perfect” ruby), in which case it will be suspected of being artificial. Dopants are added to some manufactured rubies so they can be identified as synthetic, but most need gemmological testing to determine their origin.
Imitation rubies have also been present in the gemstone market for some time. Red spinel, red garnet and even glass have been falsely named as rubies. Trade terms such as balas ruby for red spinel and rubellite for red tourmaline can mislead unsuspecting buyers. Such terms are discouraged from being used by most of the gemmological associations such as the Gemological Institute of America (GIA).
Any purchase of a ruby should be accompanied by a proper certificate that validates the stone as being a natural ruby, otherwise it is safe to assume it is a synthetic of imitation ruby.