Sunday, May 3, 2020

Geuda Heat treatment


                      Geuda Heat treatment





Detailed literature survey is presented on gem minerals, corundum family of gems, colour in gem s tones and heat treatments. Physical and chemical investigations on gem minerals are conducted to understand the nature of treatable stones. Treatable stones are characterized by the presence of different types of impurities in the basic corundum structure. Optimum heating rates, cooling rates and soaking periods are established for geuda and ottu stones. Investigations carried out on over one thousand and twenty samples revealed that certain types of geuda stones can be converted into good blue sapphires while other varieties become light blue or dark blue stones. Removal of bluish and brownish tints in red geuda A comparative stones are not completely satisfactory. Study of the Lakmini furnace with the Toda furnace was carried out to ascertain the more economic one.



Burning machine (New)


Traditional system



As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated. In a sense, humans alter all gem materials after they are found in the earth in order to prepare them for use in jewelry. Natural gem crystals are transformed from their rough crystallographic form into the shapes, outlines, and degrees of polish in the gemstones that we appreciate and wear in jewelry. These steps are and have always been the routine procedures used for manufacturing gemstones. Beyond traditional cutting and polishing, however, gems can often be treated in ways meant to alter their color or clarity. In addition to enhancing their appearance, the process may also improve (or in some cases diminish) the gem’s durability. Because these treatments are not always apparent to the unpracticed eye, and are sometimes difficult to distinguish even by experts, it is necessary and legally required for anyone selling a gem (including consumer to consumer trade) to disclose the treatment procedure it may have received.
Non-disclosure of this treatment could cause a person to believe that a particular gemstone was of higher quality naturally and therefore be more valuable than it actually is. An added challenge is that treatments can be permanent, long lasting, or short-lived under normal jewelry use. Treated gems may require special care by their owner. In the United States, the Federal Trade Commission has established a set of consumer guidelines outlining the need for treatment disclosures and special care requirements, and countries around the world either adhere to similar guidelines, or have regulations of their own. Additionally there are several professional organizations such as the AGTA or the  ICA or  CIBJO that have formulated specific guidelines that their members are required to follow regarding the disclosure of treatments in gem materials. The following glossary includes terms that are often used in the gem treatment nomenclature, and that you may encounter when shopping for gemstones. Finally, treatments for gemstones are constantly being changed and refined, and the detection of these new treated gems is an important part of ongoing gemological research.





After burning Process






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