COMPARE GUIDE
Green GlassVSSynthetic Green Sapphire
Side-by-side comparison of physical properties, fluorescence, and crystal system — to identify by observation.
- ◎ is higher in Synthetic Green Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Synthetic Green 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: Green Glass | B: Synthetic Green Sapphire | Verdict |
|---|---|---|---|
| Refractive index (RI) | 1.480–1.700 | 1.762–1.770 | B higher |
| Specific gravity (SG) | 2.30–4.50 | 3.98–4.05 | Overlap |
| Mohs hardness | 5.0–6.0 | 9.0 | B higher |
| Birefringence | — | 0.008 | — |
| Dispersion | — | — | — |
| Property | A: Green Glass | B: Synthetic Green Sapphire |
|---|---|---|
| Crystal system | 非晶質 | 六方晶系(三方晶系) |
| Pleochroism | — | 強(緑・黄緑) |
| Chelsea filter | inert | — |
| UV (long-wave) | inert | — |
| UV (short-wave) | inert | inert |
◆Green glass typically has RI 1.48–1.55, SG 2.4–4.5, isotropic (no ), with gas bubbles and . Synthetic green sapphire has RI 1.760–1.770, weak , and Mohs 9 — orders of magnitude harder and refractometer-distinct from glass.
Distinguishing tools
Tools that decide between Green Glass and Synthetic Green 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.

