Crystal

Birefr-ingence D=he-ho

Refractive index h at l= 0.63m

Thermooptical Coef.dh/dT 10^-6/K

Structure and lattice constant, ?

Melting point ^oC

Density g/cm³

Hard-ness (Moh)

Thermal Coef. 10^-6/K

TiO₂

+ 0.282

ho=2.583
he=2.865

a: -0.72
c: -0.42

Tetragonal a=4.593   c=2.958

1840

4.26

7

a: 7.14
c: 9.19

YVO₄

+ 0.222

ho=1.9929
he=2.2154

a: -8.5
c: -3.0

Tetragonal a=7.12,  c= 6.29

1825

4.22

5

a: 4.46
c: 11.37

CaCO₃

- 0.1705

ho=1.6557
he=1.4852

Rhomb.a=4.989 c= 17.062

1339

2.715

3

a:24.39
c: 5.68

TeO₂

- 0.118

ho=2.260
he=2.142

Tetragonal a=4.81 c=7.613

730

5.99

4.5

LiNbO₃

- 0.086

ho=2.286
he=2.203

a: 0.53
c: 5.60

Hexagonal
a=5.15 c=13.86

1255

4.64

5

a: 16.7
c: 2.0

SiO₂(Quartz)

+ 0.009

ho=1.5427
he=1.5518

Hexagonal
a=5.15c=13.86

1610

2.66

5

7.07