Silicon Dioxide Iron Chromium doped
SiO2:FeCr
Chemical name
Silicon Dioxide Iron Chromium doped |
Mineral name
Quartz |
Chemical formula
SiO2:FeCr |
Melting point [°C]
1700 |
Crystal system
trigonal |
Crystal Class
trigonal-trapezohedral (32) |
Space Group
P3_1 21, P3_2 21 |
Unit cell
a [Å]:4.91 b [Å]:4.91 c [Å]:5.40 |
Molecular weight [g/mol]
60.08 |
Formula units
Z=3 |
Frequent crystal surfaces
{10-11}, {01-11}, {10-10} |
Twinning
dauphine law, brazil law, japan law |
Mohs hardness
7 |
Density [g/cm3]
2.65 |
Cleavage
none |
Fracture / Tenacity
brittle, conchoidal |
Color
dark brown |
Streak
white |
Transparency
transparent to opaque |
Luster
vitreous on prismatic surfaces, resinous on fracture planes |
Optical character
uniaxial (+) |
Refractive Index
nω=1.543; nε=1.552 |
Birefringence δ
0.009 |
Pleochroism δ
none |