Fig. 32. Albite-twinned plagioclase crystals (tan, top; and yellow, bottom right) are replaced by K-feldspar (gray; bottom left) and myrmekite (left corner). Top plagioclase crystal is microfractured and also replaced in its interior by irregular islands of grid-twinned microcline (black and white). Biotite (brown). From Echo Lake granodiorite along Highway 50 near eastern edge of exposed rock north of Echo Pass and adjacent to access gravel road., a