Cathodoluminescence of natural diamond related with implanted impurities

In spectra of cathodoluminescence of natural diamonds doped by the ion implantation method for the first time the lines related with luminescence centers containing Cr, Ni, Zn, Ag and Tl atoms are revealed. The nature of these centers is discussed. The comparison of spectra of cathodoluminescence of diamonds containing an implanted Ni with those for synthetic diamonds shows that the luminescence of the latter is related with Ni, used as a synthesis catalyst