Two textures of optically negative chlorite and one of positive chlorite can be distinguished in low-grade metavolcanic rocks of the St. Anthony Complex, Newfoundland. The negative chlorite is a low-temperature polytype. Recrystallization from negative to positive chlorite was induced by deformation during and after lower-greenschist-facies metamorphism. Interlayered and intermixed positive and negative chlorites in the matrix of undeformed metavolcanic rocks of the Dunn Point Formation, Nova Scotia, are cross-cut by veins of positive chlorite. Negative chlorite has recrystallized to positive chlorite owing to rising metamorphic temperature under conditions of the prehnite-pumpellyite facies. The negative chlorite is more magnesian than the analogous chlorite in the Newfoundland rocks, and it has recrystallized to the positive form at a lower temperature.--Modified journal abstract.

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