Tellurium dioxide (TeO2) is a solid oxide of tellurium. It is encountered in two different forms, the yellow orthorhombic mineral tellurite, β-TeO2, and the synthetic, colourless tetragonal (paratellurite), α-TeO2.
T 3312 (OTTO) Tellurium oxide, 99.5% Cas 7446-07-3 - used to prepare tellurium metal, telluric acid, and many tellurium salts.