Figure 10.05. MgO-SiO₂-CaO ternary diagram. The units are weight percentages of the three oxides. Labeled in red are the chemical compositions (in weight percent units) of the normative minerals quartz (Q), enstatite (en), forsterite (fo), diopide (di), wollastonite (wo) and calcium silicate (cs). To see weight percent values for the three components and the weight percent values for the normative minerals as you mouseover the ternary diagram, click the "Show Norm" button. As with the two component system, the location of the bulk composition shows which the normative minerals will have positive values.    Return to text