Paratellurite

Tellurium dioxide (TeO2 or paratellurite) is a solid oxide of tellurium. It is used as an acousto-optic material. It forms tetragonal crystals.Tellurium dioxide is also a conditional glass former, which means it will form a glass with small molar dditions of a second compound such as an oxide or halide. TeO2 glasses have high refractive indices and transmit into the mid-infrared part of the electromagnetic spectrum, therefore they are of technological interest for optical waveguides. Tellurite glasses have also been shown to exhibit Raman gain up to 30 times that of silica, useful in optical fibre amplification.
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General Information:
 Chemical Formula:
TeO2
 Composition:
(Molecular Weight = 159.60 gm)
Tellurium 79.95 % Te
Oxygen 20.05 % O 
 Empirical Formula:
TeO2
 IMA Status:
Approved IMA 1960
Physical Properties:
 Color:
grayish white.
 Density:
5.6
 Diaphaniety:
Opaque
 Hardness:
1 - Talc
 Luster:
Resinous
 Streak:
white
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