Educational Resources & Study Guides
Reference charts, gemological diagnostic guides, optical constant tables, and study materials.
Gemological Reference Resources
Curated learning categories for gemology students and trade professionals.
Gemstone Species Guides
Refractive index, specific gravity, optic character, and inclusion profiles for major mineral families.
View Gemstone Guide →Diamond Grading Guides
Proportion calculation tables, clarity feature terminology, and fluorescence screening guidelines.
View Diamond Guide →Laboratory Instrumentation
Instrument calibration steps, immersion cell operation, and polariscope figure determination.
View Lab Methods →Discover the IGL Difference
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