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Synthetic alexandrite is an artificially grown crystalline variety of chrysoberyl, composed of beryllium aluminum oxide (BeAl 2 O 4). The name is also often used erroneously to describe synthetically-grown corundum that simulates the appearance of alexandrite , but with a different mineral composition.
Tairus (Russian: Тайрус, a portmanteau of Тайско and Русский ()) is a synthetic gemstone manufacturer. It was formed in 1989 as part of Mikhail Gorbachev's perestroika initiative to establish a joint venture between the Russian Academy of Sciences and Tairus Created Gems Co Ltd. of Bangkok, Thailand.
Alexandrite in sizes over three carats are very rare. Today, several labs can produce synthetic lab-grown stones with the same chemical and physical properties as natural alexandrite. Several methods can produce flux-grown alexandrite, Czochralski (or pulled) alexandrite, and hydrothermally-produced alexandrite.
However, the latter term is a misnomer: synthetic color-change sapphires are, technically, not synthetic alexandrites but rather alexandrite simulants. This is because genuine alexandrite is a variety of chrysoberyl: not sapphire, but an entirely different mineral from corundum. [22]
Soviet jewelry falls under the category of art, antiques and collectibles which are all grouped and defined as Movable Cultural Property. [1] [2] Although all Soviet jewelry can be called art, most of jewelry from USSR is considered to be collectibles and some, depending on the jurisdiction under which they are located, are (or soon to become) legitimate antiques.
Amber is used in jewelry and as a healing agent in folk medicine. There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions . [ 3 ]
In the 1960s, the American jewelry industry changed the definition of emerald to include the green vanadium-bearing beryl. As a result, vanadium emeralds purchased as emeralds in the United States are not recognized as such in the United Kingdom and Europe. In America, the distinction between traditional emeralds and the new vanadium kind is ...
[citation needed] This was known at the time as the Institute of Physics at the Russian Academy of Science. [6] Their breakthrough was published in 1973, and commercial production began in 1976. [7] In 1977, cubic zirconia began to be mass-produced in the jewelry marketplace by the Ceres Corporation, with crystals stabilized with 94% yttria.