Gemstones with RI 1.515
4 gemstones have a refractive index range that includes 1.515. Refractive index measures how much light bends when entering a gem — it's one of the most diagnostic properties for identification. Measured with a gemological refractometer.
| Gemstone | RI Range | SG Range | Crystal System | Optic Character |
|---|---|---|---|---|
| Amazonite | 1.514 – 1.530 | 2.54 – 2.58 | Triclinic | DR_B- |
| Chrysocolla | 1.460 – 1.630 | 2.00 – 2.40 | Amorphous | AGG |
| Coral | 1.486 – 1.658 | 2.60 – 2.70 | Aggregate | AGG |
| Lapis Lazuli | 1.500 – 1.670 | 2.70 – 2.90 | Aggregate | AGG |