Modelling changes in stable isotope compositions of minerals during net transfer reactions in a contact aureole: Wollastonite growth at the northern Hunter Mountain Batholith (Death Valley National Park, USA)

► δ18O of wollastonite rims record disequilibrium between reactants and products. ► We model δ18O using a mass balance approach, based on the wollastonite-forming reaction. ► This model successfully reproduces many measured δ18O values of wollastonite rims.