Staurolite with up to 6.5% MgO and magnesium as the dominant divalent cation is recorded from an incompletely reconstituted metatroctolite from Fiordland, New Zealand. It occurs in complex assemblages including pyrope, hornblende, spinel and corundum, and is estimated to have crystallized at about 12 kbar and 750 degrees C. The a cell edge of this staurolite (7.891 A o ) is markedly larger than that of other natural staurolites, which may be attributed to substantial substitution of Mg for Al in the "kyanite" layer of the staurolite structure. A green staurolite with 2% Cr 2 O 3 is also recorded from a mafic metatuff from Fiordland.

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