Diamond Certification Guide: IGI vs GIA for Lab-Grown Diamonds

When dealing with HPHT lab-grown diamonds, understanding certification is crucial for both jewelers and end consumers. This guide breaks down the key differences and what they mean for your business.

Major Certification Bodies

IGI (International Gemological Institute)

• Leading certifier for lab-grown diamonds
• Faster turnaround times (2-3 weeks)
• More detailed HPHT-specific reports
• Generally lower costs

GIA (Gemological Institute of America)

• Traditional leader in natural diamond certification
• Recently expanded lab-grown certification
• Higher brand recognition
• Longer processing times (4-6 weeks)

What to Look For in HPHT Certification

Essential Information

• Growth method (clearly marked as HPHT)
• Color grade (D-E-F preferred)
• Clarity grade (VVS1-VS2 optimal)
• Cut grade (Excellent/Very Good)
• Measurements and carat weight

HPHT-Specific Details

• No post-growth treatment indicators
• Absence of metallic inclusions
• Color stability confirmation
• No phosphorescence

Best Practices for Jewelers

1. **Always request certification** for stones over 0.5ct 2. **Prefer IGI** for faster inventory turnover 3. **Use GIA** for high-value pieces (2ct+) 4. **Educate customers** about HPHT certification benefits

Working with Kunlun Growth

All our HPHT diamonds come with appropriate certification options and full disclosure of growth characteristics.