THERMAL DEPENDENCE OF INTRACRYSTALLINE Fe2+-Ca2+ EXCHANGE IN METASILICATE, FERROBUSTAMITE (Ca, Fe)SiO3 T. Yamanaka et R. Sadanaga J. Phys. Colloques, 40 C2 (1979) C2-475-C2-476 DOI: 10.1051/jphyscol:19792164