Template:Poudretteite
From The Gemology Project
Poudretteite | |
---|---|
Chemical composition | KNa2B3Si12O30 Borosilicate |
Crystal system | Hexagonal |
Habit | Hexagonal and barrel-shaped etched prisms |
Cleavage | None |
Fracture | Conchoidal, splintery |
Hardness | 5-6 |
Optic nature | Uniaxial + |
Refractive index | 1.510 - 1.532 |
Birefringence | 0.016 - 0.021 |
Dispersion | Unknown |
Specific gravity | 2.50 - 2.55 |
Lustre | Vitreous |
Pleochroism | Colorless to pink, depending on body color |