Fig. 16

Ni vs Mg# trends in prograde metamorphic olivine in Zermatt samples, red symbols olivine₁ and black symbols olivine₂ (data from Fig. 8a and Additional file 3: Table S2), compared with the Sanbagawa metamorphic belt in Japan (Arai et al. 2012; Kawahara et al. 2016; Kunugiza 1982)(core to rim trends indicated with arrows). The orange field indicates the mantle array of Ni (a.p.f.u.) vs Mg# (McDonough and Rudnick 1999). Red lines show the controls of magnetite, FeNi-alloys and sulphide presence on olivine compositions that derive from the antigorite + brucite reaction