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AquamarineVSNatural Blue Sapphire
Side-by-side comparison of physical properties, fluorescence, and crystal system — to identify by observation.
- ◎ is higher in Natural Blue Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Natural Blue Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Natural Blue Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Natural Blue Sapphire, giving a numerical distinguishing point.
Note: properties whose numeric ranges do not overlap are auto-extracted. Both are measurable with a refractometer or heavy-liquid bath.
| Property | A: Aquamarine | B: Natural Blue Sapphire | Verdict |
|---|---|---|---|
| Refractive index (RI) | 1.567–1.583 | 1.762–1.770 | B higher |
| Specific gravity (SG) | 2.66–2.80 | 3.95–4.03 | B higher |
| Mohs hardness | 7.5–8.0 | 9.0 | B higher |
| Birefringence | 0.006 | 0.008 | B higher |
| Dispersion | — | — | — |
| Property | A: Aquamarine | B: Natural Blue Sapphire |
|---|---|---|
| Crystal system | 六方晶系 | 六方晶系（三方晶系） |
| Pleochroism | 強（青・無色） | 強（青・緑青） |
| Chelsea filter | inert | inert |
| UV (long-wave) | inert | inert |
| UV (short-wave) | inert | inert |
◆Aquamarine leans toward a paler greenish-blue with lower RI (1.57–1.58) and SG (~2.7), and shows a clean two-window blue/colorless dichroism rather than sapphire's stronger blue/greenish-blue split.
Distinguishing tools
Tools that decide between Aquamarine and Natural Blue Sapphire in practice.
Note: this page is auto-generated from published GIA / CGL reference values. Individual stones, treatments, and synthetics may fall outside these ranges. For a definitive identification, consult an accredited gem laboratory.