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Sometimes, sheared rocks contain (in thin sections parallel to lineation and perpendicular to the foliation) asymmetric lens-shaped coarse grains of mica oriented oblique to the dominant foliation. These have been described as mica fish (Lister & Stoke 1981). Sometimes a number of mica fish are linked together by trails of very fine mica. The acute angle between the mica fish and the foliation points towards the direction of shear. Towards each end. the tip of the mica fish bends towards the direction of shear movement, Therefore. the sense of shear can also be determined from the asymmetry.