Diamond certification or grading is a system designed to enable buyers of diamonds to judge the quality and value of the diamonds they buy, whether they are loose or mounted in jewellery. The purpose is to allow typical buyers, without significant technical knowledge to compare quality and value to make the best choices for their budget and needs.

Before diamond certification was introduced, without training and skills, buyers were entirely reliant upon the seller for all value and quality judgements. This lack of transparency tended to lead to consumers buying inferior quality products at an unnecessarily high price.

There are several leading diamond grading organisations of which HRD (Hoge Raad voor Diamant) founded in 1973 is one of the leaders in the European market.

About HRD (Hoge Raad voor Diamant)

HRD, (Hoge Raad voor Diamant – Diamond High Council) was established in 1973 as a partnership between the Belgian government and representatives of the diamond industry. The purpose was the promotion and protection of the Belgian diamond industry. In 2007 HRD Antwerp, the diamond grading, education and research business became a wholly-owned subsidiary of the Antwerp World Diamond Centre (AWDC). This is the business that provides diamond certification for diamond vendors.

HRD Diamond Grading Scales

HRD grades diamonds using the industry-standard 4Cs of Cut, Colour, Clarity and Carat.

Cut - In the HRD system, Cut is graded from Excellent to Poor with three sub-grades: proportion, polish and symmetry.

Colour–Measures the amount of yellow/brown in present in a diamond. HRD uses a scale running from D to Z with D being colourless and Z having a visible colour tint. The scale is the same as the GIA colour grading scale.

Clarity – A measure of the degree of flawing of the diamond, both internally and externally. HRD's scale has some different terms to the original devised by the GIA but has the same number of gradations.

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 – is a measure of the weight of a diamond. This measurement is the same at all grading labs.

Can You Trust HRD Gradings?

There are serious concerns in some quarters about the accuracy and consistency of HRD gradings with a reported tendency to overgrade diamonds. Over grading enables vendors to overvalue diamonds sold to retail buyers.

1. Preliminary Reports: HRD offers services that meet the needs of diamond dealers and jewellers. Usually, these services also serve the retail buyer as well. There is one exception: As with some other grading labs, HRD offers a preliminary report for grading. This service is inexpensive but does not include a full report. Only if the report data is seen as beneficial to the jeweller or merchant will a full report be generated at extra cost. This is problematic for retail buyers because it provides a clear incentive to HRD to offer reports that jewellers will want to pay for. There is a real risk that diamonds will be over graded to encourage the creation of a profitable printed report and certificate.

2. Grading Inflation and Inconsistency: A research study carried out by Rapaport, the leading diamond market information service, investigated the consistency and accuracy of several leading diamond grading laboratories found problems with HRD. Specifically, they discovered that HRD diamonds were over graded by almost 1.5 grades as compared to the industry leader, GIA. They also found a lack of consistency between the branches of HRD. Both problems render HRD reports less useful to retail buyers than reports from GIA, which demonstrated a high degree of consistency and accuracy.

Why Are Preliminary Reports, Grading Inflation And Inconsistency Problems For Diamond Buyers?

For retail buyers of diamonds, the core benefit of a grading certificate is that it enables comparison of quality and value between diamonds offered for sale by diamond dealers and jewellers. If a potential buyer cannot rely upon the information in the report, then it has no value to the buyer. Poor quality reports may even be used to mislead buyers into overpaying for inferior-quality diamonds. Here's how the trickery occurs:

1. Preliminary reports: If a grading business has a financial interest in providing reports that overstate the quality of a diamond, then the company cannot be trusted to be impartial in its reporting. Because diamond sellers can choose whether to accept and pay for a full report, there is a good reason for HRD to provide a certificate that the jeweller will be willing to pay for.

 GIA and other thoroughly reputable grading organisations will only provide           full reports. All reporting is paid for in advance of knowing the outcome of             the grading analysis. There is no incentive for such labs to offer anything             but objective, accurate grading reports and certificates. HRD has an                     incentive to be less objective and accurate.

2. Grading inflation: In principle, any two grading organisations should be expected to provide very similar reports on equal quality and type of diamonds. Consistency enables buyers to choose diamonds based upon the certificates provided for each diamond. If a diamond from HRD is over graded by two grades compared to a similar GIA diamond, the retail price is likely to be similar in each case. The problem is that a diamond that is two grades lower is worth significantly less money, even if the grade is nominally the same. The result is that for diamonds with a similar certificated grading but differing quality diamonds, the buyer will pay too much for the incorrectly graded stone.

When choosing a diamond, the certification that is attached to the stone is essential. The information on the certificate should enable you to buy a diamond of the quality you desire at a fair price. Inaccurate certification makes the task of a jewellery buyer much harder. As a rule of thumb, try to stick to diamonds with certificates from GIA. If this is not possible, in the case of HRD certifications, assume that the diamond's 'real' quality is around two grades less than the certificate states and only ever pay accordingly.