In general, F and Cl are preferentially incorporated in apatite over biotite and biotite usually contains higher amounts of F and Cl than muscovite. Similarly, biotite prefers F over amphibole, but the distribution of Cl between biotite and amphibole varies between different rock samples. Bromine contents in muscovite are below the detection limit of 0.4 渭g/g, but can reach up to 0.8 渭g/g in biotite and up to 2.5 渭g/g in apatite and amphibole.
Near-solidus effects such as fluid exsolution, diffusive re-equilibration and hydrothermal overprint may change the initial halogen distribution in the rock. Importantly, significant amounts of the whole rock's F (up to 60%) and Cl (up to 90%) may be accommodated in post-magmatic alteration phases (fluorite and Na-K-Ca-bearing sheet silicates) and fluid inclusions. Therefore, great care has to be taken when interpreting halogen contents of whole rocks and the influence of post-magmatic halogen-carriers needs to be taken into account.