HRD Report Check, How to Verify an HRD Antwerp Certificate

An HRD report tells you exactly what the lab measured. Not what the retailer says it measured. That distinction sounds subtle until you're looking at a $6,000 purchase where the listing says "F VS1" and the report says "G VS2."

HRD Antwerp, the Hoge Raad voor Diamant (High Diamond Council), has been grading diamonds since 1976. Based in Antwerp, the historical centre of the diamond trade, they produce internationally recognised reports with rigorous grading standards. In our index right now, 102,350 natural stones carry an HRD certificate, making it the third-largest certified natural lab by stone count behind GIA and IGI. Buyers encounter HRD stones regularly, particularly through European dealers.

Our broader guide on finding a diamond certificate number when a retailer hides it covers the full picture across every lab. This post narrows down to HRD specifically: how to run the check, what the report fields mean for price, and what to watch for in retailer listings.

The two steps most buyers skip one of

An HRD report check has two distinct parts.

The first is the lab's own verification. HRD Antwerp runs an online certificate verification tool on their website where you enter the report number and pull the official graded record. You'll see the certified weight, colour grade, clarity grade, cut grade (where assigned), fluorescence, polish, symmetry, and measurements. If the retailer has quoted any of those fields incorrectly, this is where you find out. To verify an HRD certificate properly, this step is non-negotiable.

The second is a cross-retailer lookup. That's what our HRD report check tool is for. Enter the report number and you see every retailer on our index currently listing that specific stone, along with their asking price. A single HRD certificate is sometimes attached to a stone listed by two or three dealers simultaneously, each at a different price. This happens constantly. Most buyers never look.

Run both steps. Neither alone is sufficient.

What the report fields mean for price

HRD uses the same 4Cs framework as GIA, with some presentational differences. Their colour scale runs D through Z. Clarity runs from IF through I3. Cut grading is available for round brilliants and assigned as Excellent, Very Good, Good, Fair, or Poor.

The field that moves price most on an HRD round is cut grade, not colour. A round brilliant with an Excellent cut trades at a meaningful premium over the same colour and clarity graded Very Good. When retailers describe cut verbally or in listing copy, they sometimes blur this. The report grade is what matters.

Fluorescence is graded None, Faint, Medium, Strong, or Very Strong. On natural HRD rounds, strong blue fluorescence typically suppresses price relative to a None-fluorescence stone at the same colour and clarity. The exact discount varies by colour grade and buyer preference. Some buyers favour strong fluorescence in D to F stones precisely for the brightness it adds outdoors. Know what the report says, not what the listing footnotes.

Polish and symmetry are graded separately. For rounds, you want Excellent or Very Good on both. A stone graded Excellent cut but Fair symmetry is not performing the way that grade implies. These aren't minor distinctions; they affect light performance and therefore resale.

Where HRD sits against the other labs

HRD natural accounts for 0.9% of the index by stone count. Median price: $2,188 per carat. That puts HRD natural fractionally above GIA natural's $2,097 per carat, which surprises some buyers who assume GIA always commands the premium.

The lab-grown HRD segment is tiny: 4,347 stones at a median of $679 per carat. HRD lab-grown isn't a market most buyers will encounter.

Lab	Origin	Stones	Share of index	Median USD/ct
IGI	Lab-grown	5,903,640	52.7%	$356
GIA	Natural	3,401,335	30.4%	$2,097
IGI	Natural	404,708	3.6%	$1,488
HRD	Natural	102,350	0.9%	$2,188
GCAL	Lab-grown	78,190	0.7%	$968
HRD	Lab-grown	4,347	0.0%	$679

The HRD natural median sitting above GIA is a composition effect, not a certification premium. Dealers based in Antwerp who submit to HRD tend to focus on higher colour and higher clarity parcels. The aggregate median reflects who's sending stones to this lab. It is not a market verdict that HRD paper is worth more than GIA paper.

That matters practically. If you're comparing an HRD-certified stone against a GIA-certified stone of nominally identical specs, don't pay a premium for the HRD certificate alone. The market doesn't award one systematically. Check actual asking prices for both, which is exactly what the cross-lab lookup surfaces.

IGI natural sits at $1,488 per carat median. That's well below both HRD and GIA natural, and reflects a documented market perception around grading consistency. HRD holds a solid middle position: broadly trusted by European dealers, accepted by major global retailers, and not subject to the discount that follows IGI-certified natural stones.

Four ways listings misquote HRD reports

These patterns come up repeatedly when we cross-check retailer listings against HRD report data.

Colour grade rounding. A stone graded H on the HRD report gets listed as "G to H colour" in a way that implies the stone might be G, when the graded colour is H. If you see a colour range in a listing, the stone doesn't have two colours. One of those letters is on the report; the other is padding.

Cut grade omission on fancy shapes. HRD assigns cut grades for round brilliants only, not for ovals, cushions, pears, or marquises. Retailers sometimes list "Excellent cut" for a fancy shape with an HRD report because HRD graded the polish and symmetry as Excellent. Polish and symmetry are not the same as overall cut grade. Know the difference before you buy a fancy shape.

Clarity inflation at the VS2 to SI1 boundary. An SI1 stone described in listing copy as "eye-clean" may genuinely be eye-clean, but that's an assessment made by whoever inspected the stone, not a statement in the HRD report. The report says SI1. Whether that particular SI1 is eye-clean depends on inclusion type and position, which the clarity plot in the report shows. Don't take the listing's word on this.

Report number omission. Some listings say "HRD certified" with no number. Without the number, an HRD diamond report check is impossible without contacting the retailer. The number should be on the physical certificate or available on request. If it isn't, ask for it in writing before you go any further.

When the retailer won't provide the number

A retailer who won't share the HRD report number before purchase warrants scrutiny. There are narrow legitimate scenarios, mainly with melee parcels or consignment inventory, but for any individually certified stone above 0.30ct, the report number should be available before you commit payment.

Ask in writing: "Please provide the full HRD certificate number as it appears on the document." If they give you a number, verify it on HRD Antwerp's website and run an HRD report lookup through our HRD decoder before you agree to anything. The decoder shows what the report fields actually say and surfaces any cross-retailer price gap for that specific stone.

If the retailer says the number is available only after purchase, that's a refusal to let you verify what you're buying. For any high-value purchase, the reasonable response is to walk away. Our free certificate verification guide covers the full process for handling this across all lab types, including how to push back on retailers who stall.

What the decoder finds that a listing doesn't show

The HRD decoder at CaratHunter translates graded specs into market context. You see not just what the lab graded, but where that exact combination of weight, colour, clarity, and cut sits in the price distribution. You can see whether you're being asked to pay above or below the market for those specific grades.

The report number lookup surfaces every active listing for that stone across 110-plus retailers. Same certificate, different dealers, different prices. The gap is sometimes notable.

For more on the structure of HRD reports and how the field labels compare to GIA's layout, the HRD and AGS certificate decoder post goes into that detail.

HRD natural sits at $2,188 per carat median against GIA's $2,097. There is no systematic market premium for HRD certification over GIA. If a retailer is pricing an HRD-certified stone above what an identical GIA-certified stone would cost, the premium is theirs, not the market's. The report number will tell you whether the specs match. The lookup will tell you whether the price does.