Immiscibility gap in the system CaSiO₃-CaFeSi₂O₆ at low temperatures

Abstract

Chemical compositions of natural iron-wollastonites formed at low temperatures thus far available are in the region of about (Ca_0.83Fe_0.17)SiO₃, and those of ferroan wollastonites have less iron content than about 5 mole % FeSiO₃. In this paper close associations of iron-wollastonite and wollastonite from the Sampo and Ohminé mines are described. Studies by EPMA and thermal experiments on the pairs make it clear that there is an immiscibility gap between iron-wollastonite and wollastonite at low temperatures.