" /> " /> " /> powder pattern fitting. The results of the different refinement procedures indicate that apatite structure can host at most 10 Mg-atom-%, which is preferentially located in one of the two crystallographically independent sites. powder pattern fitting. The results of the different refinement procedures indicate that apatite structure can host at most 10 Mg-atom-%, which is preferentially located in one of the two crystallographically independent sites. powder pattern fitting. The results of the different refinement procedures indicate that apatite structure can host at most 10 Mg-atom-%, which is preferentially located in one of the two crystallographically independent sites.