57 Fe emission Mössbauer spectroscopy has been applied to study the lattice location and properties of Fe in gadolinium gallium garnet Gd 3 Ga 5 O 12 (GGG) single crystals in the temperature interval 300–563 K within the extremely dilute (< 10− 4 at.%) regime following the implantation of 57 Mn (T 1/2= 1.5 min.) at ISOLDE/CERN. These results are compared with earlier Mössbauer spectroscopy study of Fe-doped gadolinium gallium garnet Gd 3 Ga 5 O 12 (GGG), with implantation fluences between 8× 10 15 and 6× 10 16 atoms cm− 2. Three Fe components are observed in the emission Mössbauer spectra:(i) high spin Fe 2+ located at damage sites due to the implantation process,(ii) high spin Fe 3+ at substitutional tetrahedral Ga sites, and (iii) interstitial Fe, probably due to the recoil imparted on the daughter 57∗ Fe nucleus in the β− decay of 57 Mn. In contrast to high …