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Blue TopazVSBlue Zircon
Side-by-side comparison of physical properties, fluorescence, and crystal system — to identify by observation.
Decisive distinctionsDECISIVE
- ◎ is higher in Blue Zircon, giving a numerical distinguishing point.
- ◎ is higher in Blue Zircon, giving a numerical distinguishing point.
- ◎ is higher in Blue Topaz, giving a numerical distinguishing point.
- ◎ is higher in Blue 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.
Physical propertiesPROPERTIES
| Property | A: Blue Topaz | B: Blue Zircon | Verdict |
|---|---|---|---|
| Refractive index (RI) | 1.610–1.620 | 1.925–1.984 | B higher |
| Specific gravity (SG) | 3.50–3.57 | 4.60–4.80 | B higher |
| Mohs hardness | 8.0 | 6.5–7.5 | A higher |
| Birefringence | 0.010 | 0.039 | B higher |
| Dispersion | — | 0.039 | — |
Optics & fluorescenceOPTICS & UV
| Property | A: Blue Topaz | B: Blue Zircon |
|---|---|---|
| Crystal system | 斜方晶系 | 正方晶系 |
| Pleochroism | 中（青・無色） | — |
| Chelsea filter | inert | green |
| UV (long-wave) | inert | weak (yellow) |
| UV (short-wave) | inert | inert |
ObservationOBSERVATION
◆Blue topaz has SG 3.5 and RI 1.61–1.64 with very low ; blue zircon is markedly heavier in the hand and shows dramatic that topaz never does.
Color categoriesCATEGORIES
A: Blue Topaz
Blue
B: Blue Zircon
Blue
DISTINGUISHING TOOLS · 3 ITEMS
Distinguishing tools
Tools that decide between Blue Topaz and Blue 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.