A 3.06 ct lab-grown oval listed as Super Ideal Cut, read against its IGI report on 23 October 2026: the report states polish and symmetry, no cut grade, and the jeweler publishes no limits for the label.
Maison Assay finding
On 23 October 2026, Brilliant Earth listed a 3.06 ct IGI-certified oval as "Super Ideal Cut" while its IGI report, dated 28 September 2026, stated Excellent polish, Excellent symmetry and no cut grade; Brilliant Earth's pages do not publish the proportion limits that define Super Ideal.
Not on the report we read. The IGI report for this oval states carat, colour, clarity, polish and symmetry, and has no line for a cut grade. "Super Ideal Cut" appears on the listing, and Brilliant Earth's own page does not say whether it is a laboratory grade or the jeweler's designation. That is not an error by itself: a jeweler may use its own terms. It does mean the label cannot be checked against the report.
In short:
That the stone is cut to ideal proportions and has Excellent polish and symmetry grades on the GIA scale, according to its Super Ideal page. The page applies the term to many shapes, including oval, and also says some shapes are not compatible with cut grades. It gives no table or depth limits. Its cut guide says its scale is based on the cut specifications of the certifying laboratory and that a GIA-certified diamond with an Excellent cut grade is listed as Super Ideal or Ideal. That sentence covers GIA reports with a cut grade; it does not say how an IGI oval with no cut grade is placed.
An oval brilliant, 3.06 carats, measuring 11.91 by 8.09 by 4.99 mm (length to width 1.47, computed), colour F, clarity VS2, polish Excellent, symmetry Excellent, no fluorescence, grown by chemical vapor deposition. Its proportions panel gives table 60%, total depth 61.7%, crown 13% and pavilion 44%, a medium to slightly thick faceted girdle and a pointed culet. There is no cut-grade line. The girdle share in the drawing, 4.7%, is the remainder of the depth after crown and pavilion, so it is derived, not printed.
It began to. On 10 September 2022 IGI announced that it had added a cut grade to its reports for fancy shapes, offered at its laboratories and optional for manufacturers for the first six months. In the same announcement it says the light performance of a fancy shape cannot be predicted from its proportions, which is why it assesses more than measurements. We did not find a current IGI statement on whether the grade is now required, and the report we read, dated 28 September 2026, carries none. That makes a label that rests on "ideal proportions" harder to defend for an oval than for a round.
Differently, and only one of them names its tests. Whiteflash's A CUT ABOVE page requires GIA's highest cut grade and an AGS Ideal report, then light-performance imaging and a visual review, and describes round diamonds. Blue Nile's cut page says it treats its Ideal as interchangeable with GIA's Excellent for rounds, that GIA parameters exist only for rounds, and that it estimates and assigns grades for fancy shapes from table and depth percentages without stating the ranges. Its Astor tier is GIA-graded and GemEx-certified, with no thresholds stated.
Find the cut-grade line on the lab report and read what it says. If it says nothing, the cut label is the jeweler's own judgment, which is allowed but is not the lab's. Ask the jeweler in writing what proportion limits define the label, and keep the answer with the report number (LG839647899 here).
Comparing jewelers on what they promise after the sale? See their return and resize policies side by side and the lab-grown price basket across jewelers. The FTC's wording on terms such as "properly cut" and "brilliant" is in 16 CFR Part 23.
On 23 October 2026 we read the Brilliant Earth listing page and the IGI report image it links, then read each jeweler's cut-definition page and IGI's announcement as published. This is one stone read in full; it shows how a label relates to a report, not how often. The stone may no longer be listed, so the figures are as read that day. We have not graded, appraised or handled the stone. IGI's report-check page showed a bot challenge, which we did not bypass, so we did not confirm the report through it. Next review: January 2027.
Not on the report we read. IGI report LG839647899, dated 28 September 2026, states polish and symmetry for a 3.06 ct oval and has no cut-grade line. Brilliant Earth lists the stone as Super Ideal Cut, and its pages do not say whether the term is a laboratory grade or its own designation.
Its Super Ideal page says a diamond cut to ideal proportions with Excellent polish and symmetry grades on the GIA scale. It publishes no table or depth limits and applies the term to many shapes, including oval.
IGI announced on 10 September 2022 that it added a cut grade to fancy-shape reports, optional for manufacturers for the first six months. The oval report we read, dated 28 September 2026, has none, and we found no current IGI statement on whether it is required.
Blue Nile's cut page describes Astor by Blue Nile as its top tier, GIA-graded and certified by GemEx, cut from the finest rough. It states no numeric thresholds. For fancy shapes it says it estimates cut grades from table and depth percentages.
Whiteflash's page describes round diamonds that must first earn GIA's highest cut grade and qualify for an AGS Ideal report, then pass light-performance imaging and a visual review. It estimates fewer than 1 in 10 AGS Ideal stones pass.
Open the lab report and find the cut-grade line. If it is missing, ask the jeweler in writing what limits define the label, and confirm the report on the laboratory's own report-check page using the report number printed on it.