It has been found that the chemical state of implanted ions in SiO 2 depends on local concentration and on the transport process of the implanted element. In this work we report the optical properties of high-energy Cu-implanted silica glass. 2MeV Cu + ions were implanted at room temperature (RT) in silica glass at fluences of 0.7, 3.0 and 5.0×10 16 ions/cm 2. The absorption spectra of the as-implanted samples indicated the formation of B 2 centers, but no Cu nanoparticles were formed. The photoluminescence (PL) spectra for excitation at 280 nm exhibited broad bands at 410 and 550 nm, associated with the presence of Cu + ions in the as-implanted samples. We discuss the effect of thermal annealing in air on the absorption and the emission spectra of these Cu-implanted samples, as well as the formation of copper nanoclusters from original Cu + ions.