Spatially controlled growth of oxidize cobalt and silver nanoparticles (NPs) is successfully performed in commercial soda-lime glass slides using successively field-assisted solid-state ion exchange and continuous wave ultraviolet laser exposure. Using different characterizations techniques, it is demonstrated that either CoO or Co(3)O(4)NPs are formed, depending on the laser power. The optical properties of the silver NPs are characteristic of metallic silver, which does not suffer from oxidation. The experimental process opens a new way to combine the magnetic properties of Co(3)O(4)NPs and the optical properties of Ag NPs.