COMPARE GUIDE
Color-Change GarnetVSNatural Color-Change Sapphire
Side-by-side comparison of physical properties, fluorescence, and crystal system — to identify by observation.
Decisive distinctionsDECISIVE
- ◎ is higher in Natural Color-Change Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Natural Color-Change Sapphire, giving a numerical distinguishing point.
- ◎ is higher in Natural Color-Change 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.
Physical propertiesPROPERTIES
| Property | A: Color-Change Garnet | B: Natural Color-Change Sapphire | Verdict |
|---|---|---|---|
| Refractive index (RI) | 1.745–1.760 | 1.762–1.770 | B higher |
| Specific gravity (SG) | 3.74–3.94 | 3.95–4.03 | B higher |
| Mohs hardness | 7.0–7.5 | 9.0 | B higher |
| Birefringence | — | 0.008 | — |
| Dispersion | — | — | — |
Optics & fluorescenceOPTICS & UV
| Property | A: Color-Change Garnet | B: Natural Color-Change Sapphire |
|---|---|---|
| Crystal system | 等軸晶系 | 六方晶系（三方晶系） |
| Pleochroism | — | 強（変色性に対応） |
| Chelsea filter | red / pink | red / pink |
| UV (long-wave) | inert | weak (red) |
| UV (short-wave) | inert | inert |
ObservationOBSERVATION
◆Color-change sapphire is uniaxial doubly refractive (RI 1.76–1.77) with dichroism; color-change garnet is singly refractive (RI 1.74–1.76) with no .
Color categoriesCATEGORIES
A: Color-Change Garnet
Color-change
B: Natural Color-Change Sapphire
Color-change / Blue / Purple
DISTINGUISHING TOOLS · 3 ITEMS
Distinguishing tools
Tools that decide between Color-Change Garnet and Natural Color-Change 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.