Whole-rock mass-balance calculations. (a) Outcrop at Bruce Rocks where samples were collected from unaltered grayschist (samples 1-3), altered greyschist from within carbonate alteration zones (samples 4-6), and fault breccia (samples 7-8). (b) Whole-rock geochemistry of the altered greyschist compared to the average of three unaltered greyschist samples (BRWR-1:3). Values higher than one are gained during alteration, and anything below one has been lost. The figure shows mobilization of Fe2O3, CaO, MgO, and MnO together with Sr, Y, and REE.