Figure F9. Photomicrographs of plagioclase crystals. A, B. Elongate, tabular, partially skeletal plagioclase crystals in a quickly cooled spherulitic margin (Thin Section 47; Sample 324(198)-1213B-31R-1, 2–7 cm). C, D, E, F. Thin Section 51 (Sample 324(198)-1213B-32R-4, 131–134 cm); (C, D) edge of large skeletal plagioclase xenocryst with a marginal overgrowth on the crystal termination; (E) former melt inclusions now altered to clays, some filled with titanomagnetite, in a core of large plagioclase; (F) anorthositic crystal clump with adcumulus texture developed in plagioclase, most crystals of which contain altered melt inclusions showing as small dark gray nonreflective patches. Note the overgrowth rim at the bottom of the image. A, B, and D are under cross-polarized light, C and E are under plane-polarized light, and F is under reflected light.
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