Pericline

Pericline also refers to a doubly plunging anticline or syncline.

Pericline is a form of albite exhibiting elongate prismatic crystal. Pericline twinning is a type of crystal twinning which show fine parallel twin laminae typically found in the alkali feldspars sanidine, microcline and albite. The twinning results from a structural transformation between high temperature and low temperature forms.

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