Introduction
At the bottom of every GIA Diamond Grading Report, below the clarity plot, sits a small text block that many buyers skip entirely: the comments section. It rarely contains more than two or three lines. It uses no colour coding, no diagrams, no visual emphasis. And it can change everything you thought you knew about the diamond above it.
The 4Cs grades tell you where a diamond sits on standardised scales. The clarity plot maps what the grader found and where. But neither can capture treatments, unplotted characteristics, origin determinations, or context that the grading system was not designed to encode. The comments section handles all of it — in plain text, in quiet typography, with outsized consequences for the stone's desirability and value.
This article explains every major comment type you will encounter on reports from GIA, HRD Antwerp, and IGI, what each one means, and what questions to ask when you see them. For the clarity plot that precedes these comments, see Report Clarity Plot.
Key Points
Where comments appear on the report
On a GIA Diamond Grading Report (full format), the comments section sits directly below the clarity plot, near the bottom of the first page. On the GIA Diamond Dossier (compact format), comments appear in a condensed section — the plot is omitted, making the comments even more important as the only textual context for the clarity grade.
HRD Antwerp reports include a remarks or comments field in a similar position below the grading results. IGI reports place comments near the bottom of the grading panel. Regardless of laboratory, the function is the same: disclosing information that falls outside the grading scales.
Clarity-related comments
These are the most common entries and the ones most directly relevant to the diamond's visual appearance.
"Additional clouds are not shown." The diamond contains diffuse cloudiness that cannot be represented by discrete plot symbols. This comment appears frequently on SI1 and lower grades where scattered pinpoint clusters are too numerous to map individually. It does not automatically mean the diamond appears hazy — many stones with this comment are perfectly transparent. But it is a signal to verify visually, especially if the plot looks relatively clean for its grade. See Cloud Inclusions & Transparency.
"Clarity grade is based on clouds that are not shown." This is the comment that demands attention. It means the grade-setting characteristic — the primary reason the diamond received its clarity grade — is a cloud formation too diffuse to plot. The visual impact ranges from negligible to severe. Some diamonds with this comment are eye-clean; others show noticeable milkiness or haziness that reduces brilliance. The grade alone cannot distinguish between the two outcomes. Request high-resolution photographs under multiple lighting conditions, or inspect the stone in person. See Milky Diamond and Hazy Diamond.
"Pinpoints are not shown." Scattered microscopic inclusions too numerous to plot individually. Generally less concerning than unplotted clouds — individual pinpoints rarely affect transparency. Common on SI grades where the sheer count makes plotting impractical.
"Internal graining is not shown." Crystal growth distortion visible as faint lines or texture under magnification. The diamond may display subtle optical patterns — wavy reflections or faint banding — that the plot cannot represent. Rarely visible to the unaided eye in VS and above, but worth noting on SI grades. See Internal Graining.
"Surface graining is not shown." Similar to internal graining but affecting the polished surface. May appear as faint lines under reflected light. The finish grades (polish) typically account for surface graining severity.
Treatment and enhancement disclosures
Grading laboratories are required to disclose any detected treatments. These comments change the stone's identity and value fundamentally.
"This diamond has been treated by high pressure/high temperature (HPHT) to change its colour." The diamond's colour was artificially improved. HPHT treatment is permanent and stable, but treated stones trade at significant discounts to untreated equivalents. Disclosure is mandatory under GIA, HRD, and IGI protocols and under EU consumer protection regulations.
"This diamond has been laser drilled." A laser channel was created to reach a dark inclusion, which was then bleached with acid. The inclusion becomes less visible, but the drill hole is permanent and constitutes its own clarity characteristic. Laser-drilled diamonds must be graded and disclosed as treated.
"Clarity enhanced." Fractures have been filled with a glass-like substance to reduce their visibility. Fracture filling is not permanent — it can degrade with heat (during jewellery repair) or chemical exposure. GIA does not issue grading reports for fracture-filled diamonds. If you see this comment on another laboratory's report, understand that the clarity grade reflects the enhanced state, not the diamond's natural appearance. See Care Risks for Treated Diamonds.
"This is a laboratory-grown diamond." Major laboratories now grade lab-grown diamonds on separate report formats, but the comments section reinforces the identification. For the distinction, see Natural vs Lab-Grown Overview.
Origin and identification statements
" Origin: natural." Confirms the diamond formed geologically, not in a laboratory. GIA includes this statement on reports issued from October 2020 onward as standard practice, reflecting the need for clear natural-vs-laboratory differentiation in the modern market.
Country of origin opinions (e.g., "Origin opinion: Botswana" on certain specialised reports) are separate from the natural/lab-grown determination. Geographic origin reports are not standard on routine grading reports — they require additional testing and are typically issued by request for exceptional stones.
Inscription comments
"Inscription(s): GIA 2246812345." Confirms that a microscopic laser inscription — typically the report number — exists on the diamond's girdle. The inscription lets you match the physical stone to its report under magnification. See Report Number & Inscription.
Additional inscriptions (brand logos, personal messages) may also be noted. These do not affect grading but confirm identity.
What to do when you encounter unusual comments
Not every comment fits a standard template. Laboratories occasionally add specific observations that do not map neatly to the categories above. When you see an unfamiliar comment:
- Do not ignore it. If the laboratory thought it warranted mention, it matters.
- Ask the seller to explain it. A reputable seller should be able to interpret any comment on a report they are selling against. If they cannot, consider that a warning.
- Verify the report online. All three major laboratories — GIA, HRD, and IGI — offer free online report verification. Confirm the report is authentic and that the comments match what the seller disclosed. See Online Report Verification.
- Compare comments between competing stones. Two SI1 diamonds at similar prices may tell very different stories in their comments. The one with "clarity grade is based on clouds that are not shown" warrants more scrutiny than the one with "additional pinpoints are not shown."
Comments and price
The comments section does not directly appear in any pricing algorithm, but it explains price differences that the 4Cs cannot. A 1.00 ct, G colour, SI1, Excellent cut diamond with no concerning comments will trade higher than an otherwise identical stone carrying "clarity grade is based on clouds that are not shown." Experienced buyers read comments before comparing prices — not after.
Czech Consumer Note
Under EU consumer protection regulations applicable in the Czech Republic, sellers must disclose all known treatments and enhancements. A grading report's comments section serves as the authoritative record of such disclosures. If a Czech retailer sells a diamond described as "untreated" but the accompanying report contains a treatment comment, the report takes precedence. Czech consumers purchasing from international online sellers should always verify the full report — including comments — through the issuing laboratory's website before completing a purchase.
Summary
The comments section is the grading report's fine print — and fine print is where the consequential information lives. Clarity-related comments reveal what the plot cannot show. Treatment comments change the diamond's category entirely. Origin statements confirm whether the stone is natural or laboratory-grown. Inscription notes tie the physical diamond to its documentation.
Read the comments before you compare the grades. A diamond's 4Cs tell you its position on four scales. The comments tell you whether those positions mean what you think they mean.