Fig. 4. Mineralogical properties of Napa County parent material: (A) x-ray diffractograms of vermiculite and albite plagioclase; (B) backscatter electron micrograph of Napa County parent material (Di = diopside, P = plagioclase feldspar, VR = vermiculite); (C) energy dispersive x-ray spectra (EDX) of Napa County parent material plagioclase; (D) EDX of Napa County parent material diopside; and (E) EDX of Napa County parent material vermiculite.