“…These include the corundum-fuchsite (chromian muscovite) rocks in the greenstone belts of southern Africa (Schreyer et al, 1981;Schreyer, 1988;Kerrich et al, 1987Kerrich et al, , 1988, the chromiferous quartzites of South India (Raase et al, 1983), the breunnerite (ferroan magnesite)-quartz-chromian muscovite assemblages in Newfoundland (Chao et al, 1986), the black schists and quartzites (containing chromian muscovite ± other Cr-bearing silicates) of Outokumpu, Finnish Karelia (Treloar et al, 1987a, b), the green mica schists in the Hemlo area of Ontario, Canada (Pan and Fleet, 1991), and a variety of lithologies (quartzites, biotite schist, metsomatized ultramafic rock and vein) from Northwest Nelson, New Zealand (Challis et al, 1995). The composition of chromian muscovite from the present study differs from the previously reported examples in that it contains high concentrations of Mg (with Mg/Fe mostly falling between 4 and 9) and Ni (ranging up to 9 wt% NiO).…”