Abstract
This paper reviews recent studies on the microtextures in the Ca-Mg-Fe pyroxenes whose compositions are shown on the common ‘pyroxene quadrilateral'. Two types of microtextures due to phase changes are focused on here; one is the exsolution texture formed by nucleation or spinodal decomposition process, and another is anti-phase domain structure. In this paper, we described brief supplements on the formation process of these textures. We also emphasize the importance to study on the microtextures for further understanding of the origin of the earth and planetary materials from the view points of the microtexture analysis.
