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pericline

n. A form of albite exhibiting elongated prismatic crystals.

Wikipedia
Pericline
Pericline also refers to a doubly plunging anticline or syncline.

Pericline is a form of albite exhibiting elongate prismatic crystals.

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