CaMgSi2O6-Mg2SiO4-CaAl2Si2O8 Diagram. Ternary phase diagram for melting the system CaMgSi2O6-Mg2SiO4-CaAl2Si2O8 at 0.1 MPa pressure based on data from Osborn and Tait (1952). Temperature is in degrees Celcius and composition is in weight pecent. The non-ternary spinel MgAl2O4 field has been removed to simplify the diagram. Melting temperatures of the three minerals diopside (Di), forsterite (Fo), and anorthite (An) are shown, along with temperatures of the three binary eutectics between them. The liquidus (saturation) surfaces for the three mineral are shown by temperature contours. Drag the temperature slider on the right to show isothermal sections through the diagram. Once the slider is selected, you may use up and down arrow buttons to have more control over the speed of temperature change. Click on the "Coordinates" button to see the compositions of points in the diagram as the mouse is moved over the diagram. Click on the "Show Phases" button to see the equilibrium phase assemblages of points in the diagram as the mouse is moved over the diagram. Click on the diagram to hold a particular bulk composition. Then to see how the phase assemblage changes for the selected bulk composition (shown by a white circle), click on the "Change T" button and use the temperature slider. To cancel the selected bulk composition, click on the "Animate" button. For an alternate rendition that shows the "exposed" liquidus surfaces as the temperature is lowered and the range of melt compositions decreases, click the "Show Liquidus" button: