Page:Handbook of Precious Stones.djvu/39
This page has been validated.
DISCRIMINATION OF PRECIOUS STONES.
23
| NAME. | DENSITY. | PLEOCHROISM. | HARDNESS. |
|---|---|---|---|
| Cairngorm | 2·66 | Weak | 7 |
| Beryl | 2·69 | Strong | 7¾ |
| Tourmaline | 3·11 | „ | 7¼ |
| Spodumene | 3·20 | Weak | 6¾ |
| Diamond | 3·53 | None | 10 |
| Topaz | 3·53 | Strong | 8 |
| Hessonite | 3·66 | None | 7 |
| Chrysoberyl | 3·75 | Strong | 8½ |
| Sapphire | 4·00 | „ | 9 |
| Spessartite | 4·15 | None | 7¼ |
| Golden Zircon | 4·40 | Weak | 7½ |
| Yellow Zircon | 4·67 | „ | 7½ |
| NAME. | DENSITY. | PLEOCHROISM. | HARDNESS. |
|---|---|---|---|
| Emerald | 2·70 | Strong | 7½ |
| Aquamarine | 2·70 | „ | 7¾ |
| Jade | 3·00 | Distinct | 6 |
| Tourmaline | 3·11 | Strong | 7¼ |
| Hiddenite | 3·15 | „ | 6¾ |
| Jadeite | 3·32 | Distinct | 7 |
| Diopside | 3·34 | Weak | 6 |
| Peridot | 3·40 | Strong | 6½ |
| Epidote | 3·44 | „ | 6½ |
| Spinel | 3·58 | None | 8 |
| Alexandrite | 3·65 | Strong | 8½ |
| Demantoid | 3·85 | None | 6 |
| Sapphire | 4·00 | Strong | 9 |
| Zircon | 4·05 | Weak | 7¼ |