IGI vs GIA Certified Lab Grown Diamonds: Which Certification Should You Choose?
When buying a lab grown diamond, you'll encounter two major certifications: IGI (International Gemological Institute) and GIA (Gemological Institute of America). Both are credible, but they have important differences when it comes to lab grown diamonds. Here's an honest breakdown to help you decide.
What Is Diamond Certification?
A diamond grading report (commonly called a "certificate") is an independent assessment of a diamond's characteristics by a third-party gemological laboratory. The report documents the 4Cs (cut, color, clarity, carat weight) along with additional quality factors like fluorescence and symmetry.
Certification is critical because it gives you independent confirmation that the diamond you're buying matches the specifications the seller is advertising. Without certification, you're relying entirely on the seller's word for quality claims worth thousands of dollars.
IGI: The Lab Diamond Standard
IGI has become the dominant certification lab for lab grown diamonds. There are good reasons for this:
IGI's Advantages for Lab Grown Diamonds
Specialty and Volume: IGI has certified millions of lab grown diamonds and has developed specialized expertise and grading protocols specifically for the category. Their graders have extensive experience with the unique characteristics of lab grown stones.
Consistent Grading: IGI's grading for lab grown diamonds has become more consistent over time as the lab has refined its processes for the category.
Market Acceptance: The vast majority of lab grown diamonds sold by reputable retailers carry IGI certification. Resale platforms also recognize IGI certification for lab grown stones.
Growth Records: IGI reports the growth method (CVD or HPHT) on the certificate, providing transparency about how the diamond was created.
GIA: The Traditional Prestige Standard
GIA is the world's most respected diamond grading laboratory and created the 4Cs system. For natural diamonds, GIA is the gold standard. For lab grown diamonds, GIA has a more limited track record but is gaining ground.
GIA's Approach to Lab Grown Diamonds
GIA began grading lab grown diamonds in 2020 and uses the same terminology (Excellent, Very Good, Good, etc.) for cut grades. Their reports use the phrase "Laboratory-Grown" prominently, ensuring complete transparency.
GIA certification carries significant prestige for natural diamonds and is increasingly accepted for lab grown stones, though it is not as ubiquitous in the lab diamond market as IGI.
Key Differences: IGI vs GIA for Lab Diamonds
Market Presence: IGI certifies far more lab grown diamonds. If you're shopping at most lab diamond retailers, you'll see mostly IGI certificates.
Grading Consistency: Both labs strive for consistency, but there have been reports in the industry of slight differences in how each grades certain characteristics. This is true of all grading labs to some extent.
Price: GIA certification often commands a modest price premium due to the brand's prestige, even for lab grown diamonds.
Information on Certificate: Both certificates include the 4Cs, proportions, and fluorescence. IGI has traditionally included more detail about the growth process.
Which Should You Choose?
For most lab grown diamond purchases, IGI certification is perfectly appropriate and is what you'll find on the majority of quality lab grown diamonds. There's no meaningful quality advantage to seeking GIA-certified lab diamonds over IGI-certified ones.
If you're purchasing a very high-value lab diamond (5+ carats, exceptional quality) and brand prestige matters to you, a GIA certificate might be worth seeking. But for most buyers, IGI is the clear practical choice.
At Peaceful Diamonds, all our lab grown diamonds come with IGI certification, ensuring you can verify every quality specification before purchasing.
What to Look for on a Certificate
Regardless of which lab certified your diamond, verify these key elements on the report:
- Shape and Cutting Style: Confirms what you ordered
- Carat Weight: The weight of the specific stone
- Color Grade: D-Z scale for colorless to light yellow
- Clarity Grade: FL to I3
- Cut Grade: For round brilliants, Excellent/Ideal is best
- Lab-Grown Notation: Should clearly state "Laboratory-Grown" or "Lab-Grown"
Frequently Asked Questions
Is IGI as good as GIA for lab grown diamonds?
Yes. IGI is the dominant and most specialized certification lab for lab grown diamonds. For lab grown purchases, IGI certification is entirely credible and accepted throughout the industry.
Do lab grown diamonds need to be certified?
Technically no, but you should always buy certified lab grown diamonds. Certification provides independent verification of quality claims, which is essential when spending significant money on a diamond.
Does GIA certification make a lab diamond worth more?
GIA certification can add a modest premium due to prestige, but the underlying diamond quality is what truly matters. An IGI-certified lab diamond with excellent specifications is more valuable than a GIA-certified stone with poor specifications.
What does CVD or HPHT on a certificate mean?
These are the two production methods for lab grown diamonds. CVD (Chemical Vapor Deposition) and HPHT (High Pressure, High Temperature) both produce real diamonds. The production method doesn't meaningfully affect quality or appearance.