68 



PEKCV gUENSEL 



Fig. 26. Disintegrated phenocryst of olivine, caused by high temperature oxidation. The rim 



around the olivine crystal is hematite. Within the olivine the light grains are mineral components, 



formed by exsolution. ■: 150. Los Inocentes, Masafuera. Photo P. Ramdohr. 



Fig, 27. Part of disintegrated olivine phenocryst, enlarged x 600. Against the dark background 



of olivine the exsolution product is seen in the form of small composite grains consisting of 



hematite ^Hght and a darker undefined component. Larger light grains see PI. IL Fig. i. 



Photo P. Ramdohr. 



