LiharaEvery lab diamond at Lihara comes with an IGI grading report. If you've seen that mentioned and wondered what it actually means — who IGI is, what they grade, and why it matters — this article has your answer.
Short version: IGI certification is an independent, third-party verification that the diamond you're buying is exactly what the seller says it is. It's the difference between buying a diamond on trust and buying one on fact.
Who Is IGI?
IGI stands for the International Gemological Institute. Founded in 1975 and headquartered in Antwerp, Belgium, IGI operates grading laboratories in the world's major diamond markets — New York, Mumbai, Hong Kong, Tokyo, Dubai, and more.
IGI is the largest independent gemological laboratory in the world by volume, and it has become the dominant grading authority for lab-grown diamonds specifically. While GIA (Gemological Institute of America) was the historical standard for mined diamonds, IGI moved into the lab diamond space earlier and more extensively, and today most major lab diamond retailers — including Lihara — use IGI reports as the standard.
What Does an IGI Report Actually Tell You?
An IGI grading report is a detailed document that describes a specific diamond across multiple dimensions. Here's what's on it:
The 4Cs
- Cut: How well the diamond was cut — Excellent, Very Good, Good, Fair, or Poor. For round brilliants, IGI evaluates polish, symmetry, and proportions to arrive at an overall cut grade.
- Color: A letter grade from D (completely colorless) to Z (noticeably yellow or brown). D–F is colorless, G–J is near-colorless, K+ has visible warmth.
- Clarity: A grade from Flawless (FL) to Included (I3) that describes the nature and extent of internal inclusions and surface blemishes. Key grades: FL/IF (flawless), VVS1/VVS2 (very very slightly included), VS1/VS2 (very slightly included), SI1/SI2 (slightly included).
- Carat: The exact weight of the diamond. One carat = 0.2 grams.
Additional Details
- Shape and cutting style (e.g., Round Brilliant, Oval Brilliant)
- Measurements (diameter and depth in millimeters)
- Depth % and table % (key cut proportion metrics)
- Girdle and culet description
- Fluorescence (whether the diamond glows under UV light — typically noted as None, Faint, Medium, Strong, or Very Strong)
- A clarity plot (a diagram showing the exact location and nature of any inclusions)
- Origin confirmation: For lab diamonds, IGI explicitly states "Laboratory Grown" on the report, distinguishing it from natural diamonds
IGI vs. GIA — What's the Difference?
Both IGI and GIA are legitimate, respected grading laboratories. The main practical differences:
Lab diamond specialization: IGI has graded more lab-grown diamonds than any other institution. They have the most data, the most graders with lab diamond expertise, and the most standardized process for lab-grown stones. GIA also grades lab diamonds, but IGI is the dominant lab in this space.
Consistency: No grading lab is 100% consistent — color and clarity grades are human assessments with some inherent variability. IGI is considered very consistent, particularly for lab diamonds. Some buyers note that IGI can grade slightly more generously than GIA on certain clarity grades — something worth knowing, but not a dealbreaker, as the labs are close on the whole.
Report availability: Because so many lab diamond producers work with IGI, IGI reports are more widely available for lab-grown stones. Most lab diamonds you'll encounter at reputable retailers will have IGI reports.
Why Certification Matters When Buying
Without a certification report, you're relying entirely on the seller's description of the stone. That creates several problems:
- You can't verify the color or clarity grade independently
- You can't confirm the carat weight
- You can't verify that the stone is actually a diamond (versus a simulant)
- You can't confirm whether it's lab-grown or mined (which matters for price)
- You have no documentation for insurance purposes
An IGI report resolves all of these. It's an independent third-party assessment that travels with the diamond and lets you — and any future buyer, appraiser, or insurer — verify exactly what you have. Never buy a diamond without a reputable grading report. This is the single most important piece of due diligence in the buying process.
How to Read an IGI Report
When you receive your Lihara jewelry, your IGI report will be included. Here's how to check it:
- Verify the report number: Every IGI report has a unique number. You can enter it at igi.org to verify the report is authentic and see the full digital version.
- Check the origin statement: For lab diamonds, it should say "Laboratory Grown" clearly.
- Compare the 4Cs to what you ordered: The grades on the report should match what was listed in your order.
- Note the measurements: The physical dimensions on the report should roughly match the stone in your setting.
Frequently Asked Questions
Is IGI certification the same as GIA?
They're different institutions with different histories, but both are respected, independent grading labs. For lab diamonds, IGI is the most widely used and specialized.
Does IGI certification add to the price?
The cost of grading is built into the diamond's price from the producer. At Lihara, IGI certification is included — you're not paying extra for it.
Can I get insurance based on an IGI report?
Yes. IGI reports are accepted by jewelry insurers for coverage purposes. You'll also want a separate appraisal for insurance (which appraises replacement value, not the grade itself).
What if the diamond I receive doesn't match the IGI report?
This is a serious issue and grounds for return. Always verify your report details when you receive your order. Lihara's return policy covers any discrepancy.
Shop IGI-Certified Lab Diamonds at Lihara
Every diamond at Lihara comes with an IGI grading report — studs, tennis chains, pendants, and rings. You know exactly what you're buying before it ships, and you have documentation that travels with the piece for its lifetime.