The design and operation of a unique apparatus for plasma anodization of bulk and vapor deposited metals is described. This apparatus made possible in one chamber vapor deposition of high purity metals on polished substrates, establishment of controlled glow discharges with various inert and reactive gases, and simultaneous ellipsometric and electrical measurements of the oxide films as they were being formed. The apparatus was also used for optical constant determinations at pressure of less than 1×10−10Torr after evaporation of high purity metals.