Germanium dioxide, also called germanium oxide, germania, and salt of germanium, is an inorganic compound with the chemical formula GeO2. It is the main commercial source of germanium. It also forms as a passivation layer on pure germanium in contact with atmospheric oxygen.
Molar mass：104.6388 g/mol
Appearance：white powder or colourless crystals
Melting point：1,115 °C (2,039 °F; 1,388 K)
Solubility in water：4.47 g/L (25 °C)
10.7 g/L (100 °C)
Solubility：soluble in HF,
insoluble in other acid and alkali
Magnetic susceptibility (χ)：−34.3·10−6 cm3/mol
Refractive index (nD)：1.650
Used as raw materials for the manufacture of metallic germanium and other germanium compounds, as catalysts for the manufacture of polyethylene terephthalate resins, as well as for spectral analysis and semiconductor materials.