Spinel Hercynite Mg-ferrite Mg-chromite Magnetite Jacobsite Chromite Ulvospinel
MgAl2O4 FeAl2O4 MgFe2O4 MgCr2O4 FeFe2O4 MnFe2O4 FeCr2O4 TiFe2O4
Form.Wt. 142.27 173.81 200.00 192.30 231.54 230.63 223.84 223.59
Z 8 8 8 8 8 8 8 8
CrystalSystem Cub Cub Cub Cub Cub Cub Cub Cub
PointGroup m3m m3m m3m m3m m3m m3m m3m m3m
SpaceGroup Fd-3m Fd-3m Fd-3m Fd-3m Fd-3m Fd-3m Fd-3m Fd-3m
UnitCell
a(Å) 8.0832 8.1558 8.360 8.333 8.394 8.5110 8.3794 8.536
Vol(Å3) 528.14 542.50 584.28 578.63 591.43 616.51 588.31 621.96
MolarVol 39.762 40.843 43.989 43.564 44.528 46.416 44.293 46.826
Density 3.578 4.256 4.547 4.414 5.200 4.969 5.054 4.775
Thermal Expansion(Volumetric)
alpha 24.9 15.6 20.5 16.5 20.6 9.9
a0 0.2490 0.0977 0.3108 0.1430 -0.0353 0.0513
a1 0.0000 1.9392 1.2118 1.1191 8.0591 1.5936
a2 0.0000 0.0000 -1.2773 -0.1063 0.0000 0.0000
Elastic Properties
Ks(GPa) 196.7 210.3 162.0 203.3
G(Gpa) 108.3 84.5 91.2 104.9
