How GIA Identifies Colored Stones

How GIA Identifies Colored Stones
GIA receives a varied and complex range of items for identification; everything from colored stones and pearls, unusual carvings and jewelry, to the latest in synthetics, and simulants, as well as treated gems. A significant area of activity involves the origin of color in gemstones, most notably, but far from limited to, diamonds, rubies, and sapphires.
Inspection, Care, and Handling Procedures
GIA applies the same item identification and tracking procedures to gem identification as it does to diamond grading. Each item is assigned a bar-coded label with a unique internal identification number that is used to track it throughout the process. And at every step, special inspection, care, and handling procedures serve to protect a gem’s identity and ensure it is managed with the utmost care.
Weights and Measures
This is the first stop for any gemstone. Loose gems are weighed with an electronic micro-balance that captures the weight to the fifth decimal place. Loose polished stones are also measured with an optical measuring device to determine their proportions, measurements and facet angles. Mounted stones are measured, but not weighed.
Identification
Items are then transferred to the Identification Inventory Control department for distribution to trained and experienced gemologists for servicing. Once an item is received by an initial gemologist, its recorded weight and measurements are verified, or if the item is mounted or strung, the gemologist will use manual measuring devices to determine and record necessary measurements.
Employing state-of-the-art technology in his research and identification efforts, the gemologist then performs a variety of analytical investigations, including a microscopic examination of the item, and performs all the tests required to properly determine its gemological identity and detect any treatments.
After that, the item is transferred to a second gemologist, who independently performs all necessary observations and testing. Depending on the identity and nature of the item, it may be examined by additional gemologists and research specialists.
Report Processing and Item Return
Reports are generated after all results are finalized and services have been completed. All GIA Reports are examined and proofread to ensure quality before being sent to the client.
Last, the item is placed in its original container, joined with its report, and goes through final inspection and testing to ensure that the same submitted item is returned to the client.
Items are returned either in person through the Client Services department, or via courier through the Transport Services department. All information recorded for an item remains stored in the GIA laboratory’s permanent database for future reference.
For information on how you can become a well-informed colored stone buyer, take GIA’s interactive colored stone tutorial.
https://www.gia.edu/lab-reports-services/colored-stones/index.html
http://www.gia.edu/howtobuyagemstone/00_enter.html
http://www.scribd.com/doc/115189454/4cs-Brochure
IGI's supreme position in the gemological world is no coincidence.
It is the result of continuous research, support and synergy with professionals and consumers alike. Around the world, IGI certificates bring confidence when buying or selling diamonds, gemstones and jewelry.
Total commitment to understanding consumer concerns has motivated IGI to develop comprehensive analysis and clear documentation for consumers. This empowers jewelry buyers to focus on finding precisely what they want, with full assurance in the integrity and quality of the IGI certification.
IGI is the largest organization of its kind, with offices in Antwerp, New York, Hong Kong, Mumbai, Bangkok, Tokyo, Dubai, Tel Aviv, Cavalese, Toronto, Los Angeles, Kolkata, New Delhi, Thrissur, Surat, Chennai and Shanghai . The IGI School of Gemology operates from Antwerp, Mumbai, Dubai and Cavalese, offering a variety of courses designed for professionals and consumer enthusiasts alike.
A certificate from IGI represents the all-important 5th C that no one should be without: Confidence. As the world's largest independent gem certification and appraisal institute for diamonds, colored gemstones and jewelry, IGI is a standard of excellence for industry professionals and consumers around the globe.
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