EGL USA laboratories are located in New York and Los Angeles. Working with our affiliate EGL Canada, which includes facilities in Toronto and Vancouver, we evaluate diamonds and gemstones exclusively in North America. All together, these locations comprise the EGL USA Group.
Every item is reviewed by an exceptional team of gemologists and senior gemologists, including (as applicable) color specialists, clarity experts, and cutting-edge researchers. The group includes GIA- and FGA-graduates (denoting the Gemological Institute of America and Fellow of the Gemological Association of Great Britain, respectively.) Select senior gemologists also have advanced degrees in chemistry, physics, and nanotechnology.
EGL USA laboratories utilize state-of-the-art gemological equipment, selected for its precision and non-destructive functionality (as opposed to equipment that harms stones as part of its analytical process).
For analysis of diamonds, colored gemstones, and pearls, EGL USA gemologists use microscopes with varying degrees of magnification and 10x-corrected hand loupes. Other general equipment includes: refractometers, hand spectroscopes, polariscopes, dichroscopes, long- and short-wave ultraviolet handheld units, and fiber optic instruments.
Color grading is studied using various specialized light boxes that provide appropriate lighting conditions for precise color assessment.
More advanced analysis of colored gemstones, pearls, and clarity enhanced diamonds is achieved with digital radiography using x-ray equipment.
Gemstone identification and elemental analysis is supported by x-ray fluorescence (XRF) testing originally developed for NASA.
And gemstones and treatments are identified, in part, by advanced analytic equipment
that measures frequency, wavelengths, and energies of the electromagnetic spectrum. The regions of concentration include x-ray, ultraviolet, visible, and infrared ranges. Testing is determined by both photo luminescence and raman spectroscopy, as well as other spectral devices.
Open an account online, or contact EGL USA customer service at
888 EGL USA4 (888 345 8724) or info@eglusa.us.
Part of the process of opening an account includes establishing a user name and password. Log in with this information at Access Your Account.
EGL USA is in no way connected or affiliated with any E.G.L.-named laboratories outside of North America. And, EGL USA does not provide support for the grading standards or analytical processes of those facilities.
In fact, reports issued by any E.G.L.-named company outside of North America are under a customs border ban. Simply put, EGL USA is the sole owner of the trademark EGL in the United States. E.G.L.-named laboratories outside of North America are prohibited from using the EGL trademarks in the United States.
EGL USA can not provide any service or information on such foreign reports. It is strongly recommended that customers with such reports recertify the stones and/or jewelry in the United States, to ensure that all relevant rules and regulations are respected.
A gemological report (also known as a certificate) is an independent, expert document that provides extensive information about the quality and identifying characteristics of an analyzed stone or piece of jewelry.
A gemological report provides an unbiased professional assessment of a particular stone or piece of jewelry — a key element in making an informed purchasing decision.
Not necessarily. Diamonds and gemstones are akin to commodities. Prices can change due to regular laws of supply and demand, and can vary with stone type and consumer trends.
Stones can be purchased from many sources — neighborhood stores, large outlets, or online vendors. The choice is yours. But be sure, in any case, to buy from a reputable business owner who provides gemological reports from respected independent laboratories (as well as a fair return policy). An independent report provides the information that can clarify the quality of your potential purchase.
Yes. Please send the lab a copy of the insurance or police report, along with the inscribed stone number, if one exists. If the item was previously analyzed by EGL USA, its record will be noted. If the item was not previously analyzed by EGL USA, but is of significantly unusual size or character, the lab will also look out for it. In either case, should the stone be recognized, EGL USA will notify the appropriate authorities.
EGL USA evaluates an extensive variety of loose stones — natural white and colored diamonds, colored gemstones, pearls, and white and colored lab-grown diamonds — as well as most stones in mounted jewelry. The lab can also identify select rough stones. The lab does not accept loose melee diamonds. Also, the lab strongly recommends that customers be judicious about the submission of unidentified rock-like materials. Any analysis, even if it results in a confirmation of non-gem material, will incur a charge.
Stones and jewelry can be shipped or submitted in-person to an EGL USA laboratory. Detailed instructions are available online, at Submit a Stone. New customers, please open an account at least one business day before shipping or delivering any items for analysis.
This is at the customer’s discretion. However, for mounted stones, it is not possible to provide precise measurements or weight. So, both must be estimated. Additionally, the color of the setting can impact the perceived color of a stone. Therefore, a diamond, for example, will generally receive a split color grade, indicating a narrow range of possible colors. The final report will also indicate that the stone was graded as mounting permitted. Please note: In rare instances, unmounting may be necessary to complete an evaluation.
EGL USA can accommodate the request provided that the customer calls at least two hours prior to pickup, to allow the lab to prepare the stone. The full preliminary grading charge, listed on the Price Schedule, will apply.
If a customer requires a recheck, it is always best to request the service when the item is still in the laboratory. If an item is taken from the lab and brought back, a fee will reflect the extra work done to verify that the returned item matches the original submission.
EGL USA offers a wide variety of report types and sizes. These include the Diamond Report, 10 Star Diamond Report® , Hearts & Arrows Diamond Report, Cut Grade Diamond Report, 360° Diamond Report® , Colored Diamond Report, Envira Diamond Report™, Enhanced Diamond Report, Lab-Grown Diamond Report, Colored Gemstone Report, Envira Colored Gemstone Report™, and Pearl Report.
To verify the contents of a report issued after October 2001 for diamonds, colored diamonds, diamond single-stone jewelry, or colored diamond single-stone jewelry, enter the report number and stone’s carat weight at Verify a Report.
To verify all other reports, contact EGL USA customer service at
888 EGL USA4 (888 345 8724) or info@eglusa.us.
Please note, these services confirm data only. To authenticate that a particular stone matches a full-size report, the stone and report document can be resubmitted to EGL USA.
For absolute certainty, the stone and the report document should be checked by a professional gemologist. EGL USA offers this service for its own full-size reports, as well as those of select reputable laboratories. For information on this service, contact EGL USA customer service at 888 EGL USA4 (888 345 8724) or info@eglusa.us.
Contact EGL USA customer service at 888 EGL USA4 (888 345 8724) or info@eglusa.us.
Yes. Preliminary results (sometimes known as pre-grading) summarize basic stone characteristics for customer reference. They provide a cost-effective preview of a stone’s quality.
EGL USA encourages customers to review preliminary results carefully, especially on a mounted stone for which the lab can only provide estimated measurements and weight. At a customer’s request, a senior EGL USA gemologist will recheck an item. For a piece of jewelry, in particular, the gemologist will consider the margin of estimation. There will be a cost for this service only if there is no change in the analysis result.
Yes. EGL USA’s Cut Grade Diamond Report documents exceptional round and princess cut stones. The most preferred of these are graded — based on a combined analysis of proportions, polish, and symmetry — on a scale from very good to ideal plus.
Yes. EGL USA’s 360° Diamond Report® analyzes the combined impact of brilliance, contrast, and radiance of a diamond. Each aspect is rated on a scale from poor to excellent. Superior performance in any of the three categories can yield a beautiful stone.
EGL USA can identify the country of origin for some colored gemstones, including particular rubies, sapphires, emeralds, and some tourmalines. The overlapping characteristics of some stones may make it scientifically impossible to conclusively determine their country of origin. Please be sure to confirm availability of and fees for this service prior to ordering.
Yes. EGL USA gemologists are expert at identifying various enhancements and treatments of diamonds and colored gemstones, including high pressure high temperature (HPHT), annealed, and irradiated color enhancements, as well as laser drilling, internal laser drilling, and feather- or fracture-filling clarity treatments. EGL USA was at the forefront of industry work on enhanced, treated, and lab-grown diamonds and gemstones, and has included definitive notes regarding treatments on its reports since 2001.
Yes. EGL USA’s Enhanced Diamond Report documents stones that have heightened visual appeal due to a special treatment, such as feather or fracture filling. EGL USA provides a complete evaluation of such diamonds, and clearly identifies them with laser inscriptions and unique reports.
Yes. EGL USA’s Lab-Grown Diamond Report identifies and evaluates lab-grown diamonds, also known as synthetic or man-made stones. EGL USA provides a complete evaluation of such diamonds, and clearly identifies them with laser inscriptions and unique reports.
EGL USA can provide identifying information on rough diamonds. It is impossible to provide the same level of evaluation on these as on cut and polished stones, as the characteristics of rough stones may change once they are refined.
Yes. SI3 is a clarity grade between the traditional SI2 and I1 levels; it identifies diamonds with small inclusions that are very easy to see under 10X magnification. EGL USA introduced SI3 to the diamond trade in 1992, to better serve the changing needs of the marketplace. The following year, the industry’s primary source for diamond price and market information, the Rapaport Diamond Report, officially recognized the grade. And in the years since, global industry organizations (such as the World Federation of Diamond Bourses and the International Diamond Manufacturers Association) and consumers have recognized it as well.
The website glossary and other consumer resources provide a comprehensive overview of report-related language and content. Also, classically formatted, full-size EGL USA reports include covers with relevant gemstone glossaries.
Yes. EGL USA inscribes diamonds using the most advanced cold-laser technology available.
In some instances, yes. EGL USA’s New York laboratory offers personal appointments to analyze white diamonds in the presence of a customer, either at the lab or an approved off-site location.
EGL USA is affiliated with Universal Gemological Services (UGS), an independent appraisal company. UGS offers comprehensive appraisal reports.
Where are the EGL USA gemological laboratories?
