Gemology Library
Reference optical properties the AI cross-references during authentication. Use it to interpret your scan results.
Natural Diamond
RI
2.417
Dispersion
0.044
Mohs
10
Formed deep in the earth over billions of years. Look for natural inclusions, growth zones, and characteristic refraction.
Lab-Grown Diamond (CVD/HPHT)
RI
2.619–2.654
Dispersion
0.044
Mohs
10
Identical chemistry to natural diamond. Detection requires metal flux inclusions, growth striations, or phosphorescence under UV.
Moissanite
RI
2.619–2.654
Dispersion
0.104
Mohs
9.25
Strong double refraction (facet doubling) and higher fire than diamond. A leading diamond simulant.
Cubic Zirconia
RI
2.15–2.18
Dispersion
0.060
Mohs
8–8.5
Lower refractive index than diamond; often shows excessive fire and rounded facet edges.
Sapphire (Corundum)
RI
1.762–1.778
Dispersion
0.018
Mohs
9
Aluminum oxide. Natural stones show silk (rutile needles); flame-fusion synthetics show curved striae.
Ruby (Corundum)
RI
1.762–1.778
Dispersion
0.018
Mohs
9
Red corundum. Natural inclusions and fluorescence patterns distinguish from flux-grown synthetics.
Emerald (Beryl)
RI
1.577–1.583
Dispersion
0.014
Mohs
7.5–8
Characteristic jardin (three-phase inclusions). Most are oil/fracture-filled.
Topaz
RI
1.629–1.637
Dispersion
0.014
Mohs
8
High specific gravity; pleochroic. Often irradiation-treated for color.
