Introduction
If you have read through the GIA report walkthrough in this encyclopedia, you already understand the structure of a diamond grading report: identification at the top, grades in the middle, visual detail at the bottom. An HRD Antwerp Diamond Grading Report follows the same logic. The data points are fundamentally the same — 4Cs grades, measurements, finish, fluorescence, a clarity plot, and a proportions diagram. What changes is the layout, the labelling, and a few conventions that can trip up buyers who are used to reading GIA documents exclusively.
This article walks through an HRD report section by section, noting where it matches the GIA format and where it diverges. The goal is practical: after reading this, you should be able to pick up any HRD report and extract the same information you would from a GIA one, without confusion. For background on HRD as an institution, see HRD Profile. For the general report-reading framework, see How to Read a Report.
Key Points
Report header and identification
Like GIA, HRD places its logo, report title, and report number at the top of the document. The report number is the key to verification — enter it on HRD's online portal to confirm the report is genuine and retrieve the digital record. See Online Report Verification for the process.
HRD reports also display the date of examination. The same rule applies as with GIA: grades reflect the diamond's condition at the time of assessment. A stone re-polished or damaged after the report date may no longer match its stated grades.
One difference worth noting: HRD reports carry the branding of the Antwerp World Diamond Centre (AWDC), reflecting HRD's institutional connection to the Antwerp diamond trade. This is a branding distinction, not a grading one.
Shape, cutting style, and measurements
HRD records the diamond's shape and cutting style — "Round Brilliant," "Oval Modified Brilliant," and so on — using the same terminology as GIA. Measurements appear in millimetres in the same format: minimum diameter – maximum diameter × depth for rounds, length × width × depth for fancy shapes.
There is no meaningful difference in how HRD and GIA record this information. If you can read a GIA measurements box, you can read an HRD one. See Measurements on the Report for interpretation guidance.
The 4Cs grades
HRD grades colour, clarity, and carat weight using the same scales GIA created:
Colour: D-to-Z scale. HRD historically printed traditional European colour descriptions — terms like "Exceptional White+" (D), "Exceptional White" (E), "Rare White+" (F), and "Top Wesselton" (G–H range) — alongside the letter grades. These terms come from the old Scandinavian Diamond Nomenclature that predates GIA's system and was widely used in European trade. Current HRD reports use the D-to-Z letter grade as the primary reference, though you may still encounter the European descriptors on older reports or in supplementary documentation. If you see an unfamiliar colour term on an HRD report, it maps to a specific letter grade — the letter is the one to use for comparison.
Clarity: Flawless through Included (I3), assessed at 10× magnification. The scale and criteria are the same as GIA's. See GIA Clarity Scale for the full breakdown.
Cut grade: For standard round brilliants, HRD assigns a cut grade using the same terminology — Excellent, Very Good, Good, and so on. The proportion tolerances that define each grade may differ slightly from GIA's boundaries, but the system is structurally aligned. See Cut Grade Scale for the GIA methodology that serves as the reference.
Carat weight: Recorded to the hundredth of a carat, identical to GIA's protocol.
The critical nuance: identical scales do not guarantee identical grades. The trade's general perception is that HRD colour grades sometimes run slightly more generous than GIA's — an HRD F colour might correspond to a GIA G on the same stone. This is not a rule, and many stones will receive matching grades from both laboratories. But when comparing an HRD diamond against a GIA diamond of the same stated colour grade, factor in this potential calibration difference. See Why Grading Differs Between Labs for a detailed treatment.
Finish: polish and symmetry
HRD grades polish and symmetry on the same Excellent-to-Poor scale GIA uses. The grades appear in the same section of the report, immediately following or alongside the 4Cs panel. No translation is needed here — an HRD "Very Good" polish means the same thing as a GIA "Very Good" polish. See Finish on the Report for what each grade means in practice.
Fluorescence
This is where the most common terminology confusion arises. HRD reports print "Nil" where GIA reports print "None" to indicate no visible fluorescence under ultraviolet light. The meaning is identical — the diamond showed no reaction under controlled UV examination — but buyers unfamiliar with HRD's vocabulary sometimes misread "Nil" as indicating missing data or an error.
The rest of the fluorescence scale aligns: Faint (HRD may also use "Slight"), Medium, Strong, and Very Strong. When fluorescence is present, HRD records the colour — most commonly blue, as with GIA.
If you are comparing an HRD report reading "Nil" against a GIA report reading "None," the fluorescence is the same. No adjustment needed. See Fluorescence on the Report for the full cross-laboratory terminology table.
Clarity plot
HRD includes a clarity plot on its full Diamond Grading Report, mapping inclusions and blemishes onto a schematic diagram of the stone. The symbology follows standard gemological conventions — internal characteristics and external characteristics are distinguished, and the symbols represent specific inclusion types (crystal, feather, cloud, needle, and so on).
The visual style of HRD's plot may differ from GIA's — different line weights, slightly different symbol rendering — but the information conveyed is the same. If you can read a GIA clarity plot, you can read an HRD one. The key question remains unchanged: where do the inclusions sit relative to the table, and are they likely to be visible face-up? See Clarity Plot on the Report for interpretation techniques.
Proportions diagram and data
HRD provides proportions information — table percentage, crown angle, pavilion angle, total depth, girdle thickness, culet size — on its full grading report. The data points match what GIA reports: these are the same measurements derived from the same physical geometry of the diamond.
Where HRD may differ is in presentation. GIA displays proportions as an annotated cross-section diagram with values labelled alongside a profile view of the stone. HRD has historically presented proportions data in a tabular or differently formatted layout, though the information content is equivalent. Regardless of format, the numbers themselves are what matter — crown angle and pavilion angle together tell you how the diamond handles light, and the interpretation is the same whether the data appears in a diagram or a table. See Proportions Diagram on the Report for how to evaluate these numbers.
Comments section
HRD includes a comments section for additional observations, similar to GIA's. Treatment disclosures, laser inscription notes, and supplementary grading information appear here. The same vigilance applies: read every line. Notes about additional clouds, treatments, or unusual characteristics carry the same practical weight on an HRD report as on a GIA one. See Comments on the Report for common entries and their implications.
Verification and security
HRD reports include security features — holograms, unique report numbers, and anti-counterfeiting measures — and can be verified online through HRD Antwerp's verification portal. The process is straightforward: enter the report number on HRD's website and confirm that the digital record matches the physical document. Always verify before purchasing, just as you would with a GIA report. See Online Report Verification.
Practical Tips for Czech Buyers
- Translate the labels, not the grades. When comparing an HRD report against a GIA report, map the terminology (Nil → None, Slight → Faint) but remember that the grades themselves may not be perfectly calibrated between the two laboratories.
- If the price seems low for the grade, investigate. An HRD G colour at a lower price than a GIA G colour may reflect a genuine difference in grading calibration, not a bargain. Compare what you see in the stone, not just what the report says.
- Older HRD reports may include European colour terms. If you encounter descriptions like "Top Wesselton" or "Rare White," these are traditional European equivalents of D-to-Z letter grades. Ask the seller to confirm the letter grade, or look for it elsewhere on the report.
- HRD reports are widely accepted across the EU. For diamonds sourced through Antwerp — a common supply route for Czech jewellers — an HRD report is a credible and verifiable grading document. It does not require "conversion" to be useful; it requires understanding.
Summary
An HRD Antwerp Diamond Grading Report contains the same essential information as a GIA report: identification, measurements, 4Cs grades, finish, fluorescence, a clarity plot, proportions data, and comments. The differences are in presentation and terminology, not substance. "Nil" means "None." Traditional European colour descriptions map to specific D-to-Z letter grades. Proportions data may appear in a different visual format but conveys the same measurements. The one substantive consideration is grading calibration: HRD colour grades are sometimes perceived as slightly more generous than GIA's, so when comparing stones across laboratories, let the diamond's appearance — not the letter grade alone — be your guide. Verify every HRD report online before purchase, read the clarity plot and comments with the same care you would give a GIA document, and treat the report as what it is: a detailed expert assessment from a credible European laboratory.