Gemstones
that are Colorless
| Gemstone |
Crystal
System |
Density |
Hardness |
Refractive
index |
Treatments |
| Beryl |
hexagonal |
2.72 |
7.5-8.9 |
1.577-1.583
| heat, radiation, fracture
filling, oiling |
| Corundum
|
trigonal |
4.00 |
9.0 |
1.762-1.770 |
none |
| Diamond |
cubic |
3.52 |
10 |
2.417
| radiation, drilling, fracture
filling |
| |
cubic |
2.29 |
6.00 |
1.483-1.487 |
none |
| Moonstone |
monoclinic |
2.56 |
6.0-6.5 |
1.518-1.526
| none |
| Opal |
amorphous |
2.15 |
5.0-6.5 |
1.450 |
fracture filling |
| Quartz |
hexagonal |
2.66 |
7.0 |
1.544-1.553 |
fracture filling |
| Sapphire |
hexagonal |
4.00 |
9 |
1.762-1.770 |
heat, fracture filling |
| Spinel
|
cubic |
3.60 |
8 |
1.718 |
none |
| Topaz |
orthorhombic |
8.0 |
1.619-1.627
| 3.53 |
blue is irradiated |
| Tourmaline
|
trigonal |
3.06 |
7.0-7.5 |
1.624-1.644 |
heat |
| Zircon |
tetragonal |
4.00 |
6.50 |
1.810-1.815 |
none |
|
|
|
|
