An IGI report for a lab-grown diamond is a short document written in shorthand. This guide goes through it field by field.
What the report is
IGI is a grading laboratory. Its report names the origin of the lab-grown diamond it describes and carries a report number. You can look the number up on IGI's report verification page.
A lab-grown diamond carries an IGI report only if it was submitted to IGI; some carry a supplier's grading instead. A grade means something only with its grader named, so D2 names the grader beside each grade.
The four grades: carat, color, clarity, cut
The report grades carat weight, color, clarity and cut. D2 shows each grade as the report gives it.
Cut grade: rounds and fancy shapes are graded differently
For a round brilliant, the cut grade comes from proportions. Light performance in a fancy shape cannot be predicted from proportions alone, so for years fancy-shape reports gave polish and symmetry but no cut grade.
In September 2022 IGI added a cut grade to fancy-shape reports. Its four-step system combines recommended proportions with a visual check of light performance.
An oval's cut grade and a round's are both IGI grades, reached by different methods. Compare them with that in mind.
Where a lab does not grade cut for a shape, D2 records the cut as Not graded.
Shape and cutting style
The report states the shape and the cutting style together, for example round brilliant.
Growth method and post-growth treatment
The Comments say how the lab-grown diamond was grown and what the report states about treatment.
D2 shows a report's treatment wording as the report prints it. How we handle treatment when sourcing: see lab-grown diamond sourcing.
Colored (fancy-color) lab-grown diamonds
A colored IGI report prints a fancy grade in the Color Grade field, for example Fancy Vivid Pink. Its scale runs Fancy Light, Fancy, Fancy Intense and Fancy Vivid. Clarity uses the same scale as other reports.
Many colored lab-grown diamonds, including most pink and red ones, get their color from post-growth treatment. For each colored lab-grown diamond we present, we show you who graded it and what its grading report says about treatment, or tell you it has no grading report, before you choose.
Checking a report
Where a product page lists a lab-grown diamond's IGI report, take the report number to IGI's verification page. Compare the grades, measurements and Comments with the page.
Looking for a loose lab-grown diamond? We sell them through our sourcing service: tell us what you want, and we'll search and present lab-grown diamonds that fit.
We source your lab-grown diamond
Sources
- IGI, public lab-grown diamond report PDF (pdf.igi.org), accessed 2026-09-24
- IGI, "IGI Now Issuing Cut Grade for Fancy Shapes" (igi.org), accessed 2026-09-24
- IGI public colored lab-grown diamond reports (pdf.igi.org), accessed 2026-10-08
- Gemological Institute of America, Fall 2016 review of CVD-grown lab-grown diamonds and Fall 2017 review of HPHT-grown lab-grown diamonds, accessed 2026-10-08
- 16 CFR 23.14 and 23.24, Jewelry Guides (ecfr.gov), accessed 2026-10-08