A certificate is an official document outlining the main characteristics of a diamond. The term “certificate” is a catch-all phrase describing a report created by a team of gemologist. The report can either be a diamond grading report, diamond dossier or a diamond quality document. Regardless of the type of certificate, it will provide peace of mind that the qualities of a diamond are, in fact, what they are said to be.

Grading Process

The grading process begins when the diamond arrives at a laboratory (GIA, EGL, etc.). Each diamond is then placed into a non-descript case. This ensures it's graded consistently. For example, a diamond being graded for a small independent jeweler is treated the same as a diamond from, say, Tiffany's, or another large diamond industry dealer. The case with the diamond is then given to a trained gemologist to be evaluated in tightly controlled lighting and viewing conditions.

Grading a Diamond

When a diamond is graded, it goes through the following steps:

  1. Natural or Lab-Grown: It's tested to determine if it's a natural or lab-grown stone. If it's lab-grown, it's sent off to go through different testing.
  2. Color Grading: The diamond is placed in a Master Stone kit to determine its color. There is also a new machine that is used to test diamond color called, Colorimeter, but not all laboratories use it. The less color it has, the higher the grade.
  3. Clarity: The stone is then placed on a microscope with 10x magnification to look for any flaws, such as inclusions or blemishes. Gemologists also look for signs of any treatments that have been applied. Then the grade and plot diagram is done.
  4. Cut: The diamond is placed on a small pedestal under special lighting to see how the light reflects and plays off the stone.  It's also measured for symmetry, polish and fluorescence.
  5. Carat Weight: The diamond is placed on a highly sensitive and very accurate scale and weighed to the fifth decimal place.
  6. Laser Inscription: Most certified diamonds are microscopically inscribed along the girdle. This can be a way to identify the diamond, the diamond dealer's logo or a personal inscription if requested.
  7. Certificate: The report is completed and laminated for protection and to prevent tampering.

The certificate is a report of the diamond's attributes and a permanent record of its quality.

Certificate Myths

There are many myths and misunderstandings about diamond grading reports.

These are the most common:

Misuse of the term certificate.

In the diamond industry this term gets used anytime that you have a certificate, and that's not really what it is. It's a Diamond Grading Report, Diamond Dossier or Diamond Quality Document. Even on GIA's reports, it states this fact,

“This report is not a guarantee, valuation or appraisal, and the laboratory providing this report (GIA) has made no representation or warranty regarding this report. The article described herein, or any inscription thereon.”

The point is that everyone uses the term certificate and it's a misuse of the word. To certify something is to guarantee something, and there's no guarantee.

Diamond grading reports guarantee price.

They really don't. What it does is establishes a third party to verify the statistics, facts or the quality of the diamond. It's to make sure the seller doesn't misrepresent the quality of the diamond. The price is determined on the current market, quality of the stone and carat weight.

All grading reports are the same.

There are different diamond grading report laboratories, and they grade diamonds differently. For example, an H grade may be one grade higher at one lab and lower at another. The reason for this is that diamond grading isn't standardized. The important thing to remember is that if you're comparing diamonds, only ones graded at the same laboratory will provide a consistent measurement.

Be aware of diamond dealers who use a variety of diamond grading laboratories. People in the diamond industry know which laboratory grading scale is going to make a particular diamond look more valuable. For example, one lab's grading scale may be more relaxed, or generous on color quality, while another may be more relaxed on clarity. If a diamond dealer is showing you multiple grading reports, find a different place.

Diamonds with reports are superior.

This is simply not true. Any diamond can be submitted for a grading report. Think of it like a school report card. Just because a kid received a report doesn't mean he is bright. The not-so-intelligent kids received report cards too. It's not the fact that the diamond comes with a report, but what the report says about the diamond.

A diamond grading report just assures the quality of the diamond — good and bad. Typically, cutters submit higher quality diamonds for reports. The reason they do this is, is because they are then able to sell those diamonds at a much higher price.

Diamonds with a report do not need to be appraised.

That's so far from the truth. Just because they have a report doesn't mean they don't need to be appraised. One of the reasons they need to be appraised is to be sure that the diamond you're looking at is the same diamond that was evaluated. Plus, most insurance companies require an appraisal before they will cover the diamond. You also want to be sure the diamond hasn't been damaged since the report was generated. You want to make sure the quality is still the same.

Grading report date does not matter.

It does matter. From time to time diamond grading report laboratories change their standards, or algorithms. If a diamond grading report is older than five years, it's recommended that you request a new report.

Reasons to Purchase a Certified Diamond

It's important to purchase a diamond with a certificate, or grading report. There are several ways to misrepresent a diamond's quality.

The following are a few of the diamond industry scams that can occur:

Misrepresenting Synthetic as Natural

This is considered fraud. If you purchase a diamond that you were told is a natural diamond, but it's, in fact, a synthetic, or lab grown diamond, contact the authorities. Although lab-grown diamonds are made of the same materials as a natural diamond, they are less valuable because they aren't as rare or valuable.

Heating and Radiation Treatments

Although this isn't against the law, a company that's in good standing with an accredited gemological association, should tell you what treatments a diamond has had. These treatments affect the quality of the diamond, and they are man altered quality grades. Therefore, it takes away from the diamond's rarity, which is the baseline for its value.

Misrepresenting a Diamond's Color

There are treatments available that can enhance a diamond's color, whether it's making a white diamond have less color, or artificially enhancing the color of a fancy colored diamond. These treatments are graded differently at each lab, and each lab also has a differing opinion concerning these treatments. However, this is still a man altered quality.

Misrepresenting Diamond's Carat Weight

This is straight forward fraud. Not only is it illegal, it's also highly frowned upon in the diamond industry.

Misrepresenting Diamond's Cut Quality

If a diamond doesn't have a certificate from an independent lab, the salesman can tell you a diamond has a higher cut quality than it actually does.

Misrepresenting Clarity Grade

Besides not having a certificate at all, a diamond can also come from a company-owned lab, which will inflate the grades of a diamond.

Hiding Diamond Damage

If you purchase a diamond that's already in a setting, a disreputable dealer could hide a chip, scratch or crack underneath a part of the setting, such as the prong.

Altering Diamond Grading Reports

This is considered fraud. That's why it's not only important to get a diamond appraised, but also purchase a diamond that's been certified by one of the top three laboratories. They have security systems in place to prevent tampering, and you can also go online to make sure your diamond grading report matches their evaluation. Simply input the report number and you can see a digital version of the report.

Counterfeit Diamond Grading Reports

This is also fraud, and a crime. By using the procedure mentioned above, you can make sure the documents match.

Remove Laser Inscription

Remember, the last step in grading a diamond is to include a laser inscription. If a diamond came back with a less than stellar grade, a diamond dealer can polish away the inscription and toss the report.

Unscrupulous people will prey on people's emotions attached to diamond purchases. They know the importance of a man giving a diamond engagement ring when proposing to the woman he loves. They also know the stress that can accompany such a large investment. Unfortunately, this usually means that the people who are on the tightest budgets and can't afford the financial hit, are affected the most.

Diamond certificates, or grading reports are important because they're the blueprints to the features and characteristics of the diamond you're purchasing. It's important to note that any diamond can get a certificate — it's like a label — but it's what the certificate says that's important. The certificate classifies quantifiable things, as well, as specific numeric values for ratios and proportions. One thing it doesn't tell you is if it's a beautiful diamond. You can only see a diamond's true beauty in person.

Certificates tell you a lot of things, but not everything. Be wary of stores or diamond dealers who put more emphasis on the certificate than the diamond, or what the certificate says. Certificates are useful tools and a guide to the diamonds you are comparing and will hopefully purchase.