Construct mineral equilibrium diagrams (at 25° C and 1 atmosphere) for the following mineral assemblage: gibbsite, quartz, kaolinite, halloysite, microcline, muscovite and albite. Use the free energies of formation given in the table below. For each case below, calculate the stability boundaries between all mineral pairs and plot them on a diagram. Then determine which sections of the boundaries are stable and redraft a second diagram with the stable fields labeled. Show all your calculations and annotate your procedure
Case 1. Choose log aK+ / H+ as your abscissa and log aNa+ / H+ as your ordinate for the diagram. Assume the activity of the dissolved silica is fixed at quartz saturation (i.e., assume the solution is in equilibrium with quartz).
Case 2. Choose logaK+ / Na+ as your abscissa and log aH+ as your ordinate for the diagram. Assume the activity of the dissolved silica is fixed at quartz saturation .
Table 1: Free energies of formation in kJ mol-1, at 25° C, 1 atmosphere pressure.