How Is Cordierite Formed?

Cordierite typically occurs in contact or regional metamorphism of pelitic rocks. It is especially common in hornfels produced by contact metamorphism of pelitic rocks. ... Cordierite also occurs in some granites, pegmatites, and norites in gabbroic magmas. Alteration products include mica, chlorite, and talc.

What kind of rock is cordierite?

Cordierite, also called dichroite or iolite, blue silicate mineral that occurs as crystals or grains in igneous rocks. It typically occurs in thermally altered clay-rich sediments surrounding igneous intrusions and in schists and paragneisses.

Is cordierite igneous metamorphic or sedimentary?

Cordierite is a common mineral in medium and high-grade pelitic metamorphic rocks. It is also common as porphyroblasts in hornfels found in contact metamorphic zones. Favored by low pressures or high temperatures. It is rare in igneous rocks, and may result form the assimilation of aluminous sediments.