Important group of phyllosilicate (sheet silicate) minerals with the general composition (Mg,Fe,Al)6[(SiAl)4O10](OH)8 and related to the micas; sp. gr. 2.6–3.3; soft and green; platy or tabular habit; occur in low-grade metamorphic rocks of greenschist facies and as an alteration product of ferromagnesian minerals in igneous rocks. The group includes specific minerals, e.g. clinochlore, delessite, penninite, and thuringite. Chamosite and greenalite are septichlorites which are chemically similar to the chlorites.
Subjects: Earth Sciences and Geography — Chemistry.