Which Diamond Certificate Is the Most Reliable? Does a Certified Diamond Guarantee It’s Real?
You’ve probably heard the phrase: “Buy diamonds with a certificate.” But what exactly does that mean?
A diamond certificate, or diamond grading report, is an official document issued by a gemological institute to confirm that a diamond is genuine. It details key attributes of the diamond, such as carat weight, color, clarity, and cut quality. Having a certificate not only ensures the diamond is real but also allows you to verify its quality before making a purchase.
Which Diamond Certificate Is the Best and Most Trusted?
There are several recognized institutions that issue diamond certificates, but the three most reputable and internationally accepted ones are:
1. GIA (Gemological Institute of America)
GIA is the most trusted and respected gemological laboratory in the world. It was founded in the USA and is the institute that originally created the famous 4Cs grading system (Color, Clarity, Cut, Carat).
Diamonds with GIA certificates tend to hold the highest resale value and are easier to trade or sell. GIA certificates are divided into:
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Full Reports: Typically issued for diamonds 1 carat and above.
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Dossiers (Short Reports): Usually issued for diamonds below 1 carat, with less detail but still highly reliable.
2. HRD (Hoge Raad voor Diamant)
HRD is based in Belgium and is also highly reputable. It’s recognized worldwide, though it's generally seen as second to GIA in terms of credibility. HRD certificates are more commonly issued for diamonds over 1 carat.
3. IGI (International Gemological Institute)
IGI, headquartered in Italy, has labs around the world and is widely accessible. Its certificate fees are generally lower, which makes it popular among general consumers. However, in business or investment contexts, IGI certificates are considered less prestigious than GIA.
What Size Diamond Typically Gets a Certificate?
In general, diamonds that weigh 0.30 carats or more (known in Thai as 30 "ตัง") usually come with a certificate. Here's how GIA handles this:
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0.30 to 0.99 carats: Usually get a GIA Dossier (short certificate).
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1 carat and above: Eligible for a Full GIA Report, which includes a diagram mapping the diamond’s inclusions. Some may also include a laser inscription on the girdle.
Even if a diamond is smaller than 1 carat, it can still receive a full certificate if the owner chooses to pay for it.
Is a Certified Diamond Always a Good Diamond?
Buying a certified diamond is always better than buying one without certification. The certificate guarantees:
Among all diamond certificates, GIA is considered the best and most trustworthy. However, it’s important to note:
Just because a diamond has a certificate doesn’t mean it’s high-quality.
You must be able to read and understand the certificate. Not all certified diamonds are the same—some may have excellent clarity and color, while others may fall short in one or more areas. Always review the 4Cs ratings listed in the certificate to make sure it matches your needs.