HRD Diamond Certification: How HRD Diamond Grading Works?

HRD Diamond Certification: How HRD Diamond Grading Works?

HRD Diamond Certification: How HRD Diamond Grading Works?

Posted by Sharif Khan on 19th Dec 2019

You probably already appreciate the importance of certification when shopping for diamonds. What if you’re a regular diamond shopper but don’t already understand the significance of certification? Well, you’ve been missing out on an essential consideration when buying jewelry.

But as you shall find out, not all certifications are reliable. Some come with gross inconsistencies, while others are outright invalid. It all comes down to the issuer of the certificate. The more reputable the issuing company, the more consistent their grading reports.

One such company is the Hoge Raad voor Diamant. The phrase Hoge Raad voor Diamant (HRD) is Belgian for the High Diamond Council. HRD shares the same location with a global diamond producer and explorer, De Beers. Presently, HRD is the preeminent diamond grading laboratory in Europe.

Besides diamond grading, HRD also monitors the flow of more than half of the world’s diamonds. It mostly tracks the diamond imports into and exports out of Belgium. The company is keen on developing Antwerp’s potential as a global diamond center. To that end, it continually markets the city to international public corporations and diamond organizations. HRD also endeavors to increase industry knowledge and awareness through research programs. Such programs not only target diamond grading. Instead, they cover the full spectrum of the industry, from manufacturing to processing and finally, trading.

James Allen


Hoge Raad voor Diamant was established in 1976. At the time, it was reputed as one of the world’s most reliable diamond grading laboratories. That’s primarily because their grading reports were always accurate and consistent with those from other famous institutions like the GIA. The company has upheld that reputation to date. HRD is presently headquartered in Antwerp, Belgium. The company has invested heavily in the city’s diamond wealth. For instance, the Antwerp World Diamond Centre (AWDC) is one of HRD’s chief shareholders.

Across various parts of Europe, an HRD-issued certificate is considered the GIA equivalent. That’s due to their accuracy and consistency. One reason why HRD reports are highly reliable is that the company complies with all the requirements in the International Rules for Grading Polished Diamonds, as are envisaged by the Independent Diamond Council. That means they follow globally-accepted best practices in all their diamond grading processes.

In 1996, HRD became the first gemological laboratory to receive the NBN EN ISO/IEC 17025 accreditation. Such accreditation was never easy to come by, as it was dictated by very stringent laws designed for gem labs by the International Organization for Standardization (ISO).


How HRD Diamond Grading Works

Like other diamond testing laboratories, HRD generally grades their diamonds based on the Four Cs. Each of the four elements –color, carat, cut, and clarity – is thoroughly evaluated. After that, the gemologists record their findings on the HRD report.

When grading their diamonds, HRD uses a cut scale ranging from Excellent to Poor. To carefully analyze diamonds based on cut, their gemologists thoroughly investigate the various aspects that constitute a diamond cut, namely, polish, proportions, and symmetry. Some diamond dealers often confuse a diamond cut with shape. A diamond cut refers to how the shape and polish influence the stone’s symmetry. It’s these three critical elements that HRD gemologists use to determine the overall cut of a diamond.

The proportions are useful in describing the brilliance of the diamond.

Polish shows the finish of the stone’s different facets.

And symmetry describes how proportionate the gem is under certain circumstances and parameters. Each of these three components is ranked on a scale from Fair to Excellent.

After doing away with cut, HRD experts proceed to the color. Essentially, color grading depends on the extent to which the stone is white or colorless. The lab generally grades their diamonds using the standard color scale that ranges from D to Z. A D-graded diamond is the most colorless while a Z-graded diamond has noticeable color hues.

Next, HRD evaluates the diamond’s clarity. The clarity scale indicates whether the stone has any inclusions. Remember, these blemishes affect the overall quality of the diamond. The lesser the inclusions, the higher the diamond’s quality.

HRD uses the following scale to grade their diamonds based on clarity.

●LC (Loupe-clean)

●VVS1 (Very, Very Slightly-Included 1)

●VVS2 (Very, Very Slightly-Included 2)

●VS1 (Very Slightly-Included 1)

●VS2 (Very Slightly-Included 2)

●SI1 (Slightly-Included 1)

●SI2 (Slightly-Included 2)

●P1 (Piqué (or Included) 1)

●P2 (Piqué (or Included) 2)

●P3 (Piqué (or Included) 3)

Carat weight is the last element of the Four Cs that the HRD gemologists look into. It’s probably the easiest aspect to hack. All it takes is measuring the weight of the diamond, using their gemological equipment.

But diamond evaluation doesn’t stop with the Four Cs. HRD goes a notch higher by looking into other finer details. For example, the experts examine aspects like girdle size, table width, fluorescence, finish grade, and culet.

Upon completing the entire grading process, the company writes a report. The report outlines the quality of the gem based on each component analyzed. HRD reports are some of the most comprehensive in the industry. The company strives to give a brief but precise overview of its findings. And if there are critical areas the experts never tested, those are also noted on the document. HRD guarantees the accuracy of its reports by ensuring each diamond goes through numerous tests.

For quality control, HRD only certifies diamonds that meet certain minimum thresholds. As for those that don’t meet the cut, the company distributes them to collectors, retailers, or other grading labs for further testing. However, HRD makes sure the vendors who buy such diamonds from the company maintain accurate descriptions of their flaws when selling them to their clients. That way, a consumer can purchase the gems having all facts at their disposal.

To avoid any conflicts of interest, graders never know the owners of the diamonds they’re working on.

Besides issuing diamond certificates, HRD provides the following additional services;

  1. Preliminary diamond examinations
  2. Laser inscription services
  3. Evaluation and grading of treated diamonds
  4. Grading of lab-grown diamonds
  5. Evaluation of repolished diamonds
  6. HRD Antwerp Express

Why HRD?

HRD uses innovative technology to evaluate its gems before issuing accurate grading reports. The company’s equipment department purchases some of the most sophisticated screening apparatus out there. The department then designs and fine-tunes these gadgets within the laboratory. The end products are powerful machines that deliver error-free measurements.

Secondly, the laboratory works only with professionally-trained gemologists. Therefore, you can have peace of mind knowing your project is in a safe pair of hands.

HRD is also keen on empowering the general public through its education programs. For the duration of its existence, the institution has endeavored to offer gemological training to people from all over the world. The courses are both on-campus and online.

Some of the education programs the company offers include;

  1. Rough diamond courses
  2. Polished diamond courses
  3. Pearl Course
  4. Gemology courses
  5. Diamond jewelry design courses
  6. Diamond jewelry sales courses
  7. Workshops
  8. Jewelry entrepreneurship

Besides these courses, HRD also tailor-makes programs for organizations and companies. You can hire them for professional corporate seminars or individual coaching on all matters diamonds

HRD is indeed a trailblazer in the diamond testing and grading sector. The company has made its mark in this industry for over forty years now. HRD not only focuses on gem certification. It’s also keen on empowering the general public through its holistic gemology courses.