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WHAT YOU SHOULD KNOW ABOUT CERTIFIED DIAMONDS

Where do these non-GIA labs get their credentials?
They take courses from GIA, just like any other jeweler with credentials. However, they do not have the authority to ratify diamond grades on behalf of GIA.

Do all labs grade the same?
Absolutely not, even though all use the same grading terms to sound authoritative.

The problem is that all labs (except GIA) rely on the profit from certificate sales to stay in business, which compromises their impartiality. These labs must keep clients (diamond merchants) happy by giving higher grades than the GIA would, making a diamond appear better on paper than it actually is.

On the other hand, GIA is a non-profit organization and has no such conflict of interest created by a profit motive. This is why you can trust a GIA Diamond Grading Report. After all, GIA established the grading system.

Why do stores use non-GIA grading reports?
Why would a dealer use a non-GIA lab when GIA charges the same as other labs and takes the same time to do the grading report? This is a question you ought to ask yourself when considering a "certified" diamond. The simple truth is that merchants use non-GIA labs because those labs give poor diamonds better grades than they actually should get.

Is a "certificate" a guarantee of quality?
Not at all. In fact, all certificates have strong disclaimers stating they do not guarantee anything! A typical fine print example:

"This report expresses an opinion at the time of examination of the stone. It is not a guarantee, a valuation, or an appraisal of any kind. [This grading lab ] has made no representation or warranty regarding this report or the diamond described."

Merchants that use non-GIA reports are in fact saying "you can't trust our grading so we're going to ask you to trust this third party (whom you know nothing about), and this third party will not guarantee it either"!

Do I need a certificate to make an informed purchase?
No, unless you feel you can't trust the merchant in consideration. In that case you should insist on a GIA Diamond Grading Report. However, a good jeweler will show you how to confirm diamond grades without a certificate, as well as have diamonds in stock with GIA Diamond Grading Reports, if you so desire.

What about AGS (American Gem Society) reports?
AGS reports are just as valid and authentic as GIA reports, for many of the same reasons that make GIA reporting credible. In fact, AGS reports (called Diamond Quality Documents) give more details about the cut grade than GIA reports do.

However, don't confuse an AGS report with an AGS Member Jeweler. An AGS Member Jeweler does not have power to validate grades on behalf of AGS, or issue an official AGS report.

True AGS reports are rarely used in this area.

So, how do I know what I'm buying?
Whether you're shopping for a diamond with or without a GIA (or AGS) report, ask the jeweler to show you how each grade was determined on special gemological equipment. A good jeweler will make diamond grading clear, a poor jeweler will confuse you.

Last Words
To learn more about how to make a good diamond purchase, go to our Smart Buying Tips section. We wish you the best in this most meaningful purchase and hope you will enjoy the diamond you choose for all of your life.