Fig. 6. Border of microcline megacryst (gray), showing veins of microcline penetrating albite-twinned plagioclase (white; upper right). Remnant islands of plagioclase (right side) in parallel optical continuity with adjacent, larger, albite-twinned plagioclase (white; lower right side). Larger, speckled (altered) plagioclase island (center; left side) is in parallel optical continuity with large albite-twinned plagioclase grain (light tan; bottom left). Myrmekite with very tiny quartz vermicules (nearly invisible) forms border of bottom edge of the plagioclase (tan; bottom of photo).