Pyrrhotite and pentlandite fabric studies were carried out on oriented cubes of nickel sulfide ore from the tabular Durkin and Lunnon shoots associated with the Archaean Kambalda dome. Grain sizes, grain shapes, triple junction angles and preferred dimensional and lattice orientations were determined for the monoclinic pyrrhotite. Spatial orientations were determined also for pentlandite foliation and lineation in the same samples.Two distinct pyrrhotite grain morphologies were identified. The foliated pyrrhotite comprises a flattened variety, and an equant variety occurs as microvolumes within the former. Pyrrhotite foliations are separated from pentlandite foliations by consistently small angles.The pyrrhotite and pentlandite foliations are acquired features that developed at about the same time, probably following the peak of the principal dynamo-thermal event. Subsequent deformation(s)and recrystallization produced rotations within the ores and the equant pyrrhotite that crystallized from the flattened variety.

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