Current Research

Because a diamond’s proportions have such a profound effect on its brilliance and overall appearance, GIA conducted a 15-year study to model the way light behaves within a round brilliant diamond. The result was a revolutionary cut grading system for round brilliants, incorporated into GIA Diamond Grading Reports in 2005. The Institute continues to explore the complexities of diamond cut, particularly for fancy cuts. Research into more consistent, accurate clarity grading is also under way.

Because of their rarity, naturally colored diamonds have high price-per-carat values. Fancy diamonds have enjoyed unprecedented popularity in recent years, and articulating their color and cause of color has never been more important. Research into these diamonds' color origin continues to enhance GIA's colored diamond identification services.

In addition to color-changing treatments such as irradiation and high pressure/high temperature (HPHT) annealing, GIA researchers are committed to detecting clarity enhancements such as laser drilling and fracture filling. 

Since reporting on General Electric’s first cuttable synthetic diamonds in 1971, GIA has been on the leading edge of synthetic diamond research. This includes the detection of goods produced by high pressure/high temperature (HPHT) synthesis and, more recently, chemical vapor deposition (CVD).

The geographic source of a ruby or sapphire often has a dramatic effect on its market value. Institute researchers take many steps to accurately identify the geologic and geographic sources of colored gemstones in GIA's country-of-origin reports.

Heat-treated sapphire, beryllium-diffused sapphire and glass-filled ruby are just a few examples of treated corundum. These enhancements often go undisclosed, and GIA researchers work hard to investigate these artificial enhancements and uncover the means of detecting them.

The recent discovery of naturally occurring beryllium in corundum means this material must be studied to avoid confusion with corundum that has been beryllium-diffused to alter its color.

In many cases, classical gemological methods such as the microscope, refractometer and handheld spectroscope are no longer sufficient in identifying a treated or synthetic gem material. Techniques such as absorption and luminescence spectroscopy offer more sophisticated means of gem identification. Besides improving GIA's commercially available gem instruments, development of these technologies will enhance the Institute's research and identification efforts.

The practice of coating gemstones dates back thousands of years. With technological progress, though, coatings have become more durable and harder to identify. One such product GIA continues to probe is cobalt-coated tanzanite.

This once-obscure gemstone has taken on new importance as millions of dollars worth of it have been sold on television shopping networks.

This project involves testing and recording data on the more than 2,800 gems GIA purchased from the estate of renowned Swiss gemologist Dr. Edward J. Gübelin. This data will be made publicly available for research and educational use.

To achieve an attractive and consistent color, cultured pearls are frequently treated by bleaching, dyeing or irradiation. GIA researchers track these developments and also examine rare natural pearls.