Pericline may refer to any of the following geological or mineralogical structures: A doubly plunging anticline or syncline. A form of albite exhibiting elongate prismatic crystals. Pericline twinning, a type of crystal twinning in which crystals show fine parallel twin laminae, typically found in the alkali feldspar microcline.Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, p. 100, 20th ed., The twinning results from a structural transformation between high temperature and low temperature forms.Tsatskis, I. and E.K.H. Salje (1996) Time evolution of pericline twin domains in alkali feldspars, American Mineralogist, Volume 81, pages 800-810 PDF
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