Enter RI value to identify gemstones
| Gemstone | RI Range | Birefringence |
|---|---|---|
| 💎 Diamond | 2.417 | None |
| ❤️ Ruby / 💙 Sapphire | 1.762-1.770 | 0.008 |
| ✨ Alexandrite | 1.746-1.755 | 0.009 |
| 🔮 Spinel | 1.718 | None |
| 💚 Emerald | 1.577-1.583 | 0.006 |
| 🌙 Moonstone | 1.518-1.525 | 0.007 |
| 💛 Citrine/Amethyst | 1.544-1.553 | 0.009 |
| 💎 Zircon | 1.925-1.984 | 0.059 |
| 💚 Peridot | 1.654-1.690 | 0.036 |
| 💙 Topaz | 1.619-1.627 | 0.008 |