Oxides like silica are normally insulators because the electrons are intimately associated with the individual bonds or ions.
Metals can conduct because the electrons are relatively free.
But there are oxides that can become metallic conductors, or even superconductors. According to Pauling's ideas about chemical bonds, by looking at the co-ordination of these atoms, we can usually tell something about their valence. This material has zero electrical resistance even above the temperature of liquid air - cold but easy to produce and handle. This is truly amazing, and a few years ago would have been thought impossible. This solid state chemistry is clearly responsible for the unusual electrical properties.