Zirconium Silicate
ZrSiO4
Chemical name
Zirconium Silicate
Mineral name
Zircon
Chemical formula
ZrSiO4
Melting point [°C]
2550
Crystal system
tetragonal
Crystal Class
ditetragonal-dipyramidal (4/m 2/m 2/m)
Space Group
I4_1/amd
Unit cell
a [Å]:6.59
b [Å]:6.59
c [Å]:5.94
Molecular weight [g/mol]
183,29
Formula units
Z=4
Frequent crystal surfaces
{100}, {110}, {101}
Twinning
on {101}; polysynthetic twins on {112} (shocked crystals by meteorite impact)
Mohs hardness
7.5
Density [g/cm3]
4.67
Cleavage
perfect on {110} and {111}
Fracture / Tenacity
conchoidal to uneven
Color
reddish-brown, yellow, blue, green, gray, colorless
Streak
white
Transparency
transparent to opaque
Optical character
uniaxial (+)
Refractive Index
nω=1.925-1.961; nε=1.980-2.015
Birefringence δ
0.047 - 0.055
Pleochroism δ
weak
Other
radioactive, fluorescent