) plot the chemical composition of the mineral, ca,mgsi,0, in the ternary compositional space, mgo-sio,-ca0. (3) ca0 sio mgo (i) draw the stereogram of crystal

) Plot the chemical composition of the mineral, Ca,Mgsi,0, in the ternary compositional space, MgO-SiO,-Ca0. (3) Ca0 sio Mgo (i) Draw the stereogram of crystal lass 2/m. Name the relevant crystal system. (6) The RI of a hemicylinder is 1.92. An unknown mineral is placed on the flat surface of the hemieylinder. Determine the RI of the mineral (n). (6) Refracted Refiected cident