Gemstones with SG 3.90
4 gemstones have a specific gravity range that includes 3.90. Specific gravity measures density relative to water — a key diagnostic property for gem identification. Measured by hydrostatic weighing or heavy liquids.
| Gemstone | SG Range | RI Range | Crystal System | Hardness |
|---|---|---|---|---|
| Rhodolite Garnet | 3.74 – 3.94 | 1.740 – 1.770 | Cubic | 7–7.5 |
| Malachite | 3.60 – 4.05 | 1.655 – 1.909 | Monoclinic | 3.5–4 |
| Low-Type Zircon | 3.90 – 4.10 | 1.780 – 1.815 | Tetragonal | 6–7.5 |
| Sphalerite | 3.90 – 4.10 | 2.369 – 2.500 | Cubic | 3.5–4 |