Certification
AGL: American Gemological Laboratories
AGL is a US-based laboratory known for detailed colour and treatment analysis of coloured gemstones, widely used in the American jewelry trade.
Focus on coloured stones
AGL specialises in identification and treatment analysis of coloured gemstones, including detailed colour grading terminology used by appraisers and dealers in the US market.
Treatment classification
AGL reports classify treatment extent (such as none detected, minor, moderate or significant) which can materially change a stone's valuation, particularly for ruby, sapphire and emerald.
Pairing with appraisal
Because AGL focuses on identification and treatment rather than monetary value, buyers typically pair an AGL report with a separate appraisal from a qualified appraiser for insurance or resale purposes.
Buyer checklist
- ✓ Read the treatment classification carefully, not just the headline identification
- ✓ Pair the report with an independent appraisal for value
- ✓ Confirm the report matches the stone's measurements and weight
Verification tools & references
Every Riakoob piece arrives certified, insured and covered by our 12-month value promise.
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