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Brown SapphireVSBrown Zircon
Side-by-side comparison of physical properties, fluorescence, and crystal system — to identify by observation.
- ◎ is higher in Brown Zircon, giving a numerical distinguishing point.
- ◎ is higher in Brown Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Brown Zircon, 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: Brown Sapphire | B: Brown Zircon | Verdict |
|---|---|---|---|
| Refractive index (RI) | 1.762–1.770 | 1.810–1.984 | B higher |
| Specific gravity (SG) | 3.95–4.03 | 4.00–4.70 | Overlap |
| Mohs hardness | 9.0 | 7.0–7.5 | A higher |
| Birefringence | 0.008 | 0.020 | B higher |
| Dispersion | — | 0.039 | — |
| Property | A: Brown Sapphire | B: Brown Zircon |
|---|---|---|
| Crystal system | 六方晶系（三方晶系） | 正方晶系 |
| Pleochroism | 中（茶・黄茶） | — |
| Chelsea filter | — | — |
| UV (long-wave) | — | — |
| UV (short-wave) | inert | weak (yellow) |
◆Brown zircon has RI 1.81–1.984, SG 4.0–4.7, around 0.059 producing pronounced visible at 10×, and Mohs 7–7.5 — edge wear ('paper edges') is common. Brown sapphire is Mohs 9, has RI 1.762–1.770 and a much smaller (no visible ), and shows sharp, undamaged edges. The check and a hardness or refractometer reading give an immediate separation.
Distinguishing tools
Tools that decide between Brown Sapphire and Brown Zircon 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.