Fig. 5. Veins of K-feldspar (center; light gray) in interior of albite-twinned, zoned plagioclase (black, light gray). Here, the veins crosscut the twinning and extend down to the edge of the plagioclase where veins also crosscut the twinning. From the center to the right, the light gray K-feldspar gradually changes to grid-twinned microcline at the end of the albite-twinned plagioclase crystal. One plane of the grid-twinning in the microcline is parallel to the albite twinning of the plagioclase. At left end of the plagioclase grain is an outer rim of albite, which is replaced by microcline at bottom center of the plagioclase. Biotite (brown); quartz (white, cream, gray).