End-member unmixing using the algorithm of Heslop and Dillon (2007) (doi:10.1111/j.1365-246X.2007.03432.x) was performed on 65 normalized IRM acquisition curves to quantify relative concentration changes of major magnetic mineral fractions. Four separate endmember components EM 1–4 were indicated. EM1 and EM2 represent ferrimagnetic low-coercivity components, which are saturated at 100 and 300 mT, respectively. EM3 and EM4 are still far from saturation at 500 mT and should primarily include the antiferromagnetic high-coercivity minerals hematite and goethite.