Rubellite
From The Gemology Project
| Rubellite Tourmaline | |
|---|---|
| Chemical composition | Complex borosilicate |
| Crystal system | Trigonal |
| Habit | Prismatic |
| Cleavage | None |
| Fracture | Conchoidal |
| Hardness | 7.5 |
| Optic nature | Uniaxial - |
| Refractive index | 1.62 - 1.64 |
| Birefringence | 0.014 - 0.022 |
| Dispersion | Low, 0.018 |
| Specific gravity | 3.06 |
| Lustre | Vitreous |
| Pleochroism | Weak to strong |
Rubellite is the pink to red color variety of tourmaline. The name can be applied to all species of the tourmaline group, but is generally elbaite.
"Rubellite" is a tradename and in modern teaching this is depreciated, instead it should be named red (or pink) tourmaline accompanied with the species name if determined.
Treatments
Pink tourmaline is sometimes irradiated to enhance the color to a deeper red.
