Boron and boron isotope systematics in the peralkaline Ilímaussaq intrusion (South Greenland) and its granitic country rocks: A record of magmatic and hydrothermal processes

► Fresh-sodalite rocks show high [B], whereas [B] is low in the sodalite-free samples. ► Melt [B] evolution is estimated from mineral [B] combined with partition coefficients. ► Magmatic fractionation, fluid/rock interaction and sub-solidus diffusion are recorded. ► The parental melt's B isotopic composition (−17 ‰) reveals a low-δ11B mantle source. ► Heavy B entered along the intrusive contact via meteoric fluids.