Guide
IGI Certification Explained
An IGI grading report records an individual stone's measured and graded characteristics. When a selected Sula stone includes an IGI report, review the report number and exact specifications before purchase.
What Is IGI?
The International Gemological Institute (IGI) is an independent gemological laboratory that issues grading reports for natural and laboratory-grown diamonds.
A grading report describes the examined stone. It is not a warranty, appraisal, or replacement for checking that the report number, measurements, and selected product all agree.
What Does an IGI Certificate Include?
Stone-Specific Report
The report applies to one examined diamond and carries its own report number.
Grading Details
The report can record carat, color, clarity, measurements, finish and cut information where applicable.
Inscription Record
If the girdle is laser-inscribed, the report records the inscription for comparison under magnification.
Origin Disclosure
A laboratory-grown diamond report identifies the stone as laboratory grown.
Your Certificate Includes:
Carat weight (to the hundredth)
Color grade (D–Z scale)
Clarity grade (FL–I3 scale)
Cut grade (Excellent–Poor, if applicable)
Polish and symmetry grades
Fluorescence information, when reported
Exact dimensions (length × width × depth)
A unique report number and any recorded inscription
IGI vs GIA: What Is the Difference?
IGI and GIA both issue independent diamond grading reports, but their report formats and terminology are not identical. Compare the grade, measurements, proportions, comments, and inscription shown on the specific report rather than treating the laboratory name as a substitute for reviewing the stone.
How to Verify Your Certificate
Each IGI grading report carries a report number that can be checked in IGI's official verification tool.
- 1
Find the report number printed on the grading report
- 2
Open IGI’s official report-verification page
- 3
Enter your certificate number in the verification tool
- 4
Compare the online record with the report and the selected stone’s measurements
Why Certification Matters
It gives you a comparison record. The report lets you compare the stated carat, color, clarity, measurements, and finish with the stone selected for the ring.
It separates grading from valuation. A grading report describes quality characteristics; it does not set a retail price or insurance replacement value.
Keep it with your records. An insurer or appraiser may ask for the grading report alongside a receipt or appraisal. Confirm the documentation your own insurer requires.
Before You Buy
Check whether the selected stone includes an IGI grading report
Match the report number and measurements to the selected stone
Read comments, growth-method disclosures, and treatment disclosures where present
Confirm any inscription shown on the report before relying on it
Use the selected product and stone records as the source for current specifications
Ask Sula Bridal to resolve any mismatch before purchase
Want to Review a Stone Report?
Ask for the report tied to the stone you are considering and compare its specifications before purchase.
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Review and sources
Written and reviewed by Sula Bridal. Last reviewed August 3, 2026. Product availability and grading-report details can vary by selected stone; confirm the exact specifications shown before purchase.