Template:Rock Crystal
From The Gemology Project
Revision as of 19:52, 9 February 2007 by Tom Goodwin, G.G. (talk | contribs) (Edited "Clear" to Colorless. "Clear" is expected to be confused with clarity rather than color.)
Rock Crystal (Colorless Quartz) | |
---|---|
Chemical composition | SiO2 Silicon dioxide |
Crystal system | Trigonal |
Habit | Prismatic |
Cleavage | Poor |
Fracture | Conchoidal |
Hardness | 7 |
Optic nature | Uniaxial + |
Refractive index | 1.544 - 1.553 |
Birefringence | 0.009 |
Dispersion | Low, 0.013 |
Specific gravity | 2.65 |
Lustre | Vitreous |
Pleochroism | None |