Diamond Certification

A diamond certificate (also called a "diamond grading report") is a document containing the characteristics about the diamond that will make up its value. It is the pedigree that goes with the diamond and becomes a valuable document in case of loss because it will ensure that your insurance company will replace your stone with another certified stone of like quality. Certificates are not appraisals since they do not contain any information regarding the value or price of a diamond.

Grading laboratories like the GIA measure and grade diamonds sent to them by wholesalers and retailers. They provide documents called certifications describing the diamond.

The GIA also educates gemologists but just because a gemologist graduated from the GIA educations program does not mean they are somehow qualified to "certify" a diamond. Many diamond shoppers mistakenly think that just because a person graduated from a GIA class, that their opinion in any way "certifies" a diamond. Respected grading labs to not sell diamonds since that would be a conflict of interest.

Certified Diamonds

There are no laws that regulate how diamonds are graded. There are differences among different grading companies and organizations. TOG deals with certified/graded diamonds from the most respected labs: GIA, EGL and AGS.

GIA - Gemological Institute of America:

The GIA Lab is the most common and sets the industry standard for COLOR and CLARITY grading.

GIA Gem Trade Laboratories (GIA)

The Gemological Institute of America (GIA), an independent nonprofit organization, was the first organization in the U.S. to provide lab certificates for diamonds. From 1953, when Richard T. Liddicoat created and introduced the International Diamond Grading System™ which has become the standard for diamond grading worldwide.

G.I.A. Gem Trade laboratories issue a diamond grading report. This report provides great details on the diamond and offers a diagram of internal and external characteristics or flaws. It is the fingerprint that uniquely identifies that particular diamond and which could be used later to verify that diamond. Because G.I.A. grades only natural diamonds, those who purchase diamonds with a G.I.A. Diamond Grading Report will be assured that their diamond will not be a synthetic (man-made) or clarity enhanced (fractured filled) diamond. These are the two prevalent problems facing the consumer in this high-tech era.

GIA is a highly respected Lab, but at this point they do not get into cut grading as thoroughly as the AGS. The very rare "excellent, excellent" report from GIA will sell for more or less the same as AGS triple ideal. The diamond industry views the AGS and GIA as the two premier grading laboratories.

Advice: While GIA certifications are highly respected, they do not include many aspects of diamond cut that would be helpful for customers (i.e., crown height percentage, pavilion depth percentage, crown angle, pavilion angle), especially those seeking ideal cut round brilliant diamonds. Try to get a Sarin report along with the certification that shows this information

The Diamond Dossier®, is issued for diamonds weighing less than 1 carat.

EGL - European Gemological Laboratory:

The EGL certification is typically less demanding than the GIA grading report. Their grading system may be more lenient.

European Gemological Laboratories (EGL)

The European Gemological Laboratory, Inc. (EGL) opened its first grading laboratory in Antwerp, Belgium in 1974 and subsequently opened laboratories in New York, Los Angles, Johannesburg, Paris, Istanbul, London, Israel and Seoul. The EGL introduced the SI3 clarity grade that really is just the high-end I1 quality. The EGL certifications include crown height percentage and pavilion depth percentage which are very helpful specifications in determining quality of cut.

In addition to diamond certifications, the EGL also issues a condensed report on a diamond known as a consultation. In this document, only the carat weight, color grade, clarity grade and a plotting diagram is recorded. The difference between the consultation and the certification is that it does not have depth percentage, table percentage, polish, symmetry or fluorescence grades.

Advice: While the vast majority of EGL certifications are accurate with regard to color and clarity, occasionally we see some where the color grades are higher than our determination. It just points out why our personal inspection is so important for every diamond, regardless of the certification.

AGS - American Gem Society

The AGS certification uses a diamond grading system that ranks cut, color, and clarity on a zero to 10 scale with zero being the most rare and desirable and 10 being the least desirable.

AGS Gemological Laboratories (AGS)

The American Gem Society (AGS) was founded in 1934 by Robert M. Shipley, who also founded the Gemological Institute of America (GIA). The AGS is dedicated to consumer protection through established standards of ethical business practices and the continuing education of its wholesale and retail members.

In the early 1990's, an AGS Ad Hoc Committee recommended the development of a Diamond Grading Laboratory to quantify and popularize all of the factors that affect a diamond's value and beauty. In addition to the Carat Weight of the diamond, the AGS' Diamond Grading System rates Cut, Color, and Clarity on a scale of 0 through 10, with 0 being the rarest and most desirable and 10 being the least desirable.

Although the AGS Diamond Grading System was developed in the early 1960's, it took technological advancements in the early 1990's to make it economically feasible to quantify the most important of the 4 C's - Cut. Prior to this time, Diamond Grading Laboratories did not quantify the quality of a diamond's cut.

In 1996, the American Gem Society Laboratory became a reality. Over the next few years, the AGS Ideal 0 cut grade became the new international standard for diamond beauty and value. A diamond that achieves an AGS Ideal 0 cut grade epitomizes the factors that make a diamond maximally beautiful. Those factors are brilliance, dispersion (fire), and scintillation.

Advice: We find AGS to be very good at color and clarity grading. If you want the top grade possible in a round diamond, look for an AGS triple ideal that has ideal proportions, ideal polish and ideal symmetry. This takes all the guess work out of finding a great cut diamond.

International Gemological Institute (IGI)

The International Gemological Institute (IGI) has now developed into the largest independent gem certification and appraisal institute renowned for its quality services, extensive experience and know-how. IGI, the oldest institute of its kind in Antwerp, was set up in 1975 and along with its sister laboratory in New York, is one of the leading gemological institutions in the world.

Advice: We seldom see an IGI certified diamond on the wholesale market. They have targeted the retail market and seem to be the predominate certification in retail mall jewelry stores and large chains. Because we do not inspect many IGI certified diamonds, we withhold judgement as to their consistency and accuracy.

Diamond High Council (HRD)

The Hoge Raad Voor Diamant (The Diamond High Council) is best known as the HRD. The officially recognized representative of the Belgium diamond trade and industry, the HRD headquarters are located in Antwerp, World Diamond Center.

Copy Cat Paperwork

There are numerous laboratories and companies that have created documents that look very similar to the format of the GIA diamond grading reports. They also have names and initials that are so similar to GIA that it is obvious they are trying to look like GIA documentation. This paperwork is prevalent on eBay and in jewelry stores across the country.

Prices of Diamonds

The cost of a diamond is based on color, clarity, carat weight, cut, certification and seller markup characteristics.

It is important to remember that since there is a limited supply of large high quality diamonds, rarity drives the cost equation. As a shopper you have to understand your own motives for purchasing a diamond. If you are the type of shopper who must have the top of the line in cars and expense is no object, you probably will want a VVS clarity and D-F color diamond. You feel you can afford to pay a premium for rarity and prestige, even if you can't see the difference. On the other hand, if you only want to invest in the quality you can see, VS2-SI1 clarity and G-I color will have similar beauty but are less rare and therefore less costly.

As with any shopping, you should be seeking value which is the relative measure of what you paid compared to what you received. Diamonds with high prices can be good or poor values depending on how they satisfy your needs. Likewise, diamonds with low prices can be good or poor values depending on whether you will be thrilled with the purchase. The prices for diamonds are based more on rarity than beauty. There are high price premiums for high clarity grades that have no impact on the appearance of the diamond. In particular, there is a very large premium for D color and Internally Flawless where the price is about double that of VS1 or VS2 clarity diamonds that look the same to the eye.

What to spend on a diamond

When you start to think about buying a diamond—and the love it will symbolize—you naturally want the best you can afford and a beautiful stone you will treasure forever.

Diamonds can be found in a range of prices—and you're certain to find one within the TOG extensive inventory that suits your taste and budget. If you're about to buy a Diamond Engagement Ring, you may want to consider spending the commonly accepted guideline of two months’ salary. But it's up to you to settle on a diamond that will truly represent your deepest emotions and the promise for the future you will share.

Care: Protecting Your Diamond

Even though diamonds are the hardest substance known to man, a diamond will scratch another diamond. So it is important that jewelry not be stored together since it can be scratched or tangled. Also, diamond jewelry should never be worn while doing heavy work. Points are vulnerable to chipping and even everyday activity can loosen a setting. This is why it’s important to visit a professional jeweler every six months to have your diamond’s mountings and settings checked. With proper care, your diamond jewelry will last a lifetime. Here are some tips to keep your jewelry looking fabulous:

Clean diamonds and most color gemstones in warm, soapy water with a soft toothbrush. Rinse completely and dry with a clean, soft cloth.
Remove your jewelry before showering, swimming, cleaning, sleeping, doing rough work or handling harmful chemicals - including hair care products and perfume.
Do not expose gemstone jewelry to sudden temperature changes, which may cause cracks.
Store each piece of jewelry separately to prevent them from scratching each other.

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