Water Absorption and High Electric Conductivity in betha-PbO2 and   Ag5Pb2O6
  Water absorption in lead peroxide betha-PbO2 and Bystroem-Evers compound Ag2[Ag3Pb2O6] has been investigated by infrared spectrometry and electric conductance measurements. Hydrated Ag5Pb2O6 exhibits, between room temperature and 690 K, electric conductivity, at least, order of magnitude higher than pure silver. 
D. Djurek, Z. Medunic, M. Paljevic, and A. Tonejc