Cone-shaped domain adjacent to a porphy-roclast or porphyroblast in the direction of the foliation and usually composed of another mineral than the por-phyroclast or -blast. It forms by rearrangement of material in response to inhomogeneous deformation of the matrix adjacent to the porphyroclast or -blast. Strain shadows are usually massive or contain equidimensional crystals; if they contain fibres, the term strain fringe is used instead. A mantled porphyroclast differs from a strain shadow in that the mantle has the same mineral composition as the porphyroclast and is inferred to have formed at the expense of the porphyroclast by recrystallisation
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