| CORUNDUM SAPPHIRE / RUBY |
 |
 |
 |
 |
| Name | Sapphire and ruby |
| Formula | Al2O3 |
| Hardness (Mohs) | 9 |
| Density | 3.99-4.10 |
| Crystal System | Trigonal |
| Colour | Blue, purple, yellow, green |
| Lustre | Diamond lustre, greasy lustre on less transparent crystals |
| Associated minerals | Cordierite, spinel, zircon |
| Overall size of mineral specimen | sapphire 22 x 17 x 17 millimetres ruby 10 x 8 x 10 millimetres |
| Location | Sapphire from Tanzania ruby from Zaire |
Copyright © www.finnishspectrolite.com. All Rights Reserved.
Korukivihiomo Kiurunen, Tyrrintie 129, 45410 UTTI, Finland, Tel. / Fax +358 5 368 4784, Tel. +358 40 704 8862