GIA Diamond Certificate

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Why do I need a GIA Diamond Certificate?

A diamond “Cert” otherwise known as a diamond grading report, is an independent opinion of quality in a gemstone. Most high quality diamonds and some valuable colored gemstones are likely to have them as a matter of confidence and convenience for the buyer. It's important to note that not all diamond grading reports are equal. The G.I.A. Diamond Grading Report is considered the best and most reliable independent grading report for diamonds. There are other laboratories, including the E.G.L. (European Gem Lab) and the HRD (Hoge Raad voor Diamant) in Antwerp. Beware of copycat, look-alike reports! There are a number of questionable “knock off” reports that sound similar to the legitimate labs, especially on the internet. When in doubt, contact us to talk to one of our diamond experts.


GIA, The Gold Standard.

The Gemological Institute of America (G.I.A.) is the jewelry industry’s best and most respected source of education and certifications (grading reports.) There are 2 branches of G.I.A, the laboratory services and education divisions. G.I.A.'s laboratory services division issues independent grading reports on diamonds and colored gemstones. The G.I.A. education division is the most prestigious and universally recognized institute of learning in jewelry and gemology fields. An advanced degree from the G.I.A. is called a G.G. (Graduate Gemologist degree.) Christopher and Villi are both “G.G.’s”

View / Download Reports GIA Certified Gemstones and Diamonds Reports Chicago Christopher Duquet Evanston Illinois


VIEW / DOWNLOAD How to Read a Diamond Grading Report

VIEW / DOWNLOAD How to Read a Diamond Dossier

EGL, Gemologist Laboratory

EGL is a name used by numerous independently affiliated gemological laboratories around the world, both in the USA and overseas. The US based lab is generally considered the most reliably accurate lab, but can vary in opinion from the GIA in some cases. Other labs, especially EGL international and EGL Isreal can vary significantly from GIA standards and have garnered controversy recently. The negative perception of these labs has led many stores and institutions in the US to avoid using these labs.

HRD, Antwerpt

This is the gemological laboratory under the umbrella of the Antwerp Diamond Council, which represents the Belgian diamond industry. These reports are slightly different than GIA or any others in their format and terminology, but are reliably accurate and ethical. They are not widely seen in the US most probably due to the dominance of GIA and the limited influence of Antwerp in the US market.

AGS, American Gem Society

This is an American based independent gemological laboratory associated withe the trade organization American Gem SocietyThe AGS offers trading reports Ising a different methodology than the GIA, which states quality designations in letters. The AGS uses a number system, and is therefore not as widely used as the GIA system of grading. The AGS is none the less very scientific and ethical and accurate in their reports. The AGS reports are less popular than GIA, primarily due to the universally recognized character of the GIA system.

IGI International Gemological Institute

This Laboratory is much more popular outside the United States, and is not widely used in the American market. Their reports are generally considered less reliable and substandard to GIA or AGS reports. This Lab uses "valuations" which are highly unusual, greatly inflated, and generally disregarded by the trade.

PGS Professional Gem Sciences

This is a highly regarded Independent Laboratory in Chicago. It is Ethical and precise and used GIA methodology and standards. They serve both the trade and consumers and provide a high level of service on a "walk in" basis.

BS, Made up certificate names

Anybody can make up a fake name and publish it on the internet. Remember that there's a lot of mischief out there and you should work with someone you can trust!

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