Figure F4. Linear regression plots of measured weight percent vs. average peak area from X-ray diffraction. Plots on the left show results for random bulk powders (see Fig. F2 for diffractograms). Plots on the right show results for oriented clay-sized aggregates (see Fig. F3 for diffractograms). Correlation coefficients are shown as r-values. See Tables T3 and T6 for error analysis.