Crystallographic
Syngony	Cubic
Symmetry Class	m3m
Lattice Constants	a = 4.026 Å c = a
Cleavability	(100), perfect

Optical
Refractive Index at ne	1.3931
Refractive Index at nF' - nC'	0.0040
Thermal Coefficient of Refractive Index at 3.39 microns for ±60 °C	(-1.25) ... (-1.51) x 10-5
Transmission Range, microns	0.12 - 6.5

Thermal
Thermal Linear Expansion, °C-1 for ±60 °C	(28.1 ... 34.8) x 10-6
Thermal Conductivity, W/(m * °C) at 38 °C	14.2
Specific Heat Capacity, J/(kg * °C)	1.5617 x 103
Melting Point, °C	870

Mechanical
Density, g/cm3 at 20 °C	2.60
Mohs Hardness	4
Vickers Microhardness, Pa	98 x 107
Constants of Elastic Compliance, Pa-1	S11 = 11.32 x 10-12 S12 = -3.06 x 10-12 S44 = 15.91 x 10-12
Young Modulus (E), Pa
in <100> direction	8.84 x 1010
in <111> direction	14.22 x 1010
Shear Modulus (G), Pa
in <100> direction	4.09 x 1010
in <111> direction	6.29 x 1010
Poisson Ratio	0.270

Chemical
Molecular Weight	25.94
Solubility
in water, gram/100 cm3	0.27
in acids	soluble

Ref. Index vs. Wavelength l
Wavelength, Microns	Refractive Index
0.2	1.439
0.5	1.3943
1.0	1.3871
2.0	1.3788
3.0	1.3666
4.0	1.3494
5.0	1.3266
6.0	1.2975
7.0	1.262
8.0	1.218
9.0	1.165
10.0	1.101

Internal Transmittance t i (l) vs. Wavelength l
Wavelength, Microns	Internal Transmittance
0.2	0.90
0.5	0.98
1.0	0.97
3.0	0.97
5.0	0.88
6.0	0.65
7.0	0.14

Custom sizes and specifications are available on request.