Nickel-pigmented anodic aluminum oxide, Ni-Al2O3 was pyrolytically coated with tin oxide (SnO2). The undesirable increase of reflectance in the solar spectrum due to the high refractive index of the SnO2 film was compensated by an antireflection layer. The layer was applied by a simple dipping technique in a bath containing a commercial colloidal silica sol which forms a silica (SiO2) layer. The infrared reflectance is nearly unaffected by the silica sol treatment process. Preliminary test results indicate that treated samples are resistant to temperatures as high as 300 degrees C as well as to corrosion in an 8% sulfuric acid solution. In addition, the optical properties were unaffected by outdoor exposure for two months.